datavorous/entrance-exam-dataset huggingface dataset:
Which of the following Statements is a tautology?

Options:
A \((\sim q \wedge p) \wedge q\)
B \((\sim q \wedge p) \wedge(p \wedge \sim p)\)
C \((\sim q \wedge p) \vee(p \vee \sim p)\)
D \((p \wedge q) \wedge[\sim(p \wedge q)]\)

The correct answer is:
\((\sim q \wedge p) \vee(p \vee \sim p)\)

Solution:
In this problem, 2 statements exist, \(p\) and \(q\). Both can be true or false. Hence, there can be 4 possibilities.
\(\begin{array}{|l|l|}
\hline \mathbf{p} & \mathbf{q} \\
\hline \mathrm{T} & \mathrm{T} \\
\hline \mathrm{T} & \mathrm{F} \\
\hline \mathrm{F} & \mathrm{T} \\
\hline \mathrm{F} & \mathrm{F} \\
\hline
\end{array}\)
The first choice is: \((\sim q \wedge p) \wedge q\)
\(\begin{array}{|l|l|l|l|l|}
\hline p & q & \sim q & \sim q \wedge p & (\sim q \wedge p) \wedge q \\
\hline T & T & F & F & F \\
\hline T & F & T & T & T \\
\hline F & T & F & F & F \\
\hline F & F & T & F & F \\
\hline
\end{array}\)
The second choice is \((\sim q \wedge p) \wedge(p \wedge \sim p)\)
\(\begin{array}{|l|l|l|l|l|l|l|}
\hline \mathbf{p} & \mathbf{q} & \sim \mathbf{q} & \sim \mathbf{q} \wedge \mathbf{p} & \sim \mathbf{p} & \mathbf{p} \wedge \sim \mathbf{p} & (\sim \mathbf{q} \wedge \mathbf{p}) \wedge(\mathbf{p} \wedge \sim \mathbf{p}) \\
\hline \mathrm{T} & \mathrm{T} & \mathrm{F} & \mathrm{F} & \mathrm{F} & \mathrm{F} & \mathrm{F} \\
\hline \mathrm{T} & \mathrm{F} & \mathrm{T} & \mathrm{T} & \mathrm{F} & \mathrm{F} & \mathrm{F} \\
\hline \mathrm{F} & \mathrm{T} & \mathrm{F} & \mathrm{F} & \mathrm{T} & \mathrm{F} & \mathrm{F} \\
\hline \mathrm{F} & \mathrm{F} & \mathrm{T} & \mathrm{F} & \mathrm{T} & \mathrm{F} & \mathrm{F} \\
\hline
\end{array}\)
The third choice is \((\sim q \wedge p) \vee(p \vee \sim p)\)
\(\begin{array}{|l|l|l|l|l|l|l|}
\hline \mathbf{p} & \mathbf{q} & \sim \mathbf{q} & \sim \mathbf{q} \wedge \mathbf{p} & \sim \mathbf{p} & \mathbf{p} \mathbf{\sim} \mathbf{p} & (\sim \mathbf{q} \wedge \mathbf{p}) \vee(\mathbf{p} \vee \sim \mathbf{p}) \\
\hline \mathrm{T} & \mathrm{T} & \mathrm{F} & \mathrm{F} & \mathrm{F} & \mathrm{T} & \mathrm{T} \\
\hline \mathrm{T} & \mathrm{F} & \mathrm{T} & \mathrm{T} & \mathrm{F} & \mathrm{T} & \mathrm{T} \\
\hline \mathrm{F} & \mathrm{T} & \mathrm{F} & \mathrm{F} & \mathrm{T} & \mathrm{T} & \mathrm{T} \\
\hline \mathrm{F} & \mathrm{F} & \mathrm{T} & \mathrm{F} & \mathrm{T} & \mathrm{T} & \mathrm{T} \\
\hline
\end{array}\)
A tautology is a statement that is always true.
Choice 3 is the right answer.

Topic: Mathematics, Mathematical Reasoning, JEE Main
Which of the following statements is (are) incorrect?

(i) Percentage ionic character in CsCl bond is ~55% . (Electronegativity values of Cs and Cl are 0.7 and 3.0 respectively)

(ii) From H2O to H3O+ , the geometry around O atom changes drastically.

(iii) The most stable oxidation state for element with atomic number 113 is expected to be +2.

(iv) The 2nd ionization energy of Ca is greater than 1st ionization energy of it but lower than 2nd ionization energy of K.

Options:
A Only i
B i, ii, iii
C ii, iii
D iii, iv

The correct answer is:
ii, iii

Solution:
(a) Ionic character
% ionic character=16( x A − x B )+3.5 ( x A − x B ) 2
where, x A − x B =Difference in electro-negativity of bonded atoms. 16×(3.0−0.7)+3.5× (3.0−0.7) 2 =55.32%

(b) Geometry for both the species is tetrahedral, as in both 'O' is s p 3 hybridised
c 113=Rn 5f146d107s27p1= Due to inert pair effect 7 s 2 electron do not take part in bond formation, so, most stable oxidation state is +1.
(d) Successive ionization energies are higher for every element. 2nd ionization of K happens from 3s23p6 configuration which is an inert gas configuration and for Ca it happens from 4s1. So, K has higher second ionisation energy than Ca.

Topic: Chemistry, Classification of Elements and Periodicity in Properties, JEE Main
Which of the following statement(s) is (are)
incorrect reason for eutrophication?
(A) excess usage of fertilisers
(B) excess usage of detergents
(C) dense plant population in water bodies
(D) lack of nutrients in water bodies that prevent plant growth

Choose the most appropriate answer from the options given below :

Options:
A (A) only
B (C) only
C (B) and (D) only
D (D) only

The correct answer is:
(D) only

Solution:
The process in which nutrient enriched water bodies support a dense plant population which kills animal life by depriving it of oxygen and results in subsequent loss of biodiversity is known as eutrophication.

Topic: Chemistry, Environmental Chemistry, JEE Main, JEE Main 2021 (17 Mar Shift 2)
Which of the following statements is correct?

Options:
A If fx is an odd function, then gx=∫axftdt is an even function.
B If fx is an odd function, then gx=∫axftdt is also odd.
C If fx is a periodic function, then gx=∫axftdt is also periodic.
D If fx is periodic, then gx=∫axftdt is always non - periodic.

The correct answer is:
If fx is an odd function, then gx=∫axftdt is an even function.

Solution:
As, gx=â«0xftdt
âg-x=â«0-xftdt
Put t=-u
âdt=-du
â´g-x=-â«0xf-udu
â«0xfudu
(as f x is odd)
â´g-x=gx
Hence, gx is even.
Also, Consider gx=â«0xcos2â¡tdt
âgx=x2+sinâ¡2x4
Which is non - periodic even though y=cos2â¡x is periodic
Also, if gx=â«0xcosâ¡tdt
Then, gx=sinâ¡x, which is periodic.

Topic: Mathematics, Definite Integration, JEE Main
Which of the following statements is correct?

Options:
A BCl3 and AlCl3 are both Lewis acids and BCl3 is stronger than AlCl3
B Both BCl3 and AlCl3 are Lewis acids and AlCl3 is stronger than BCl3
C Both BCl3 and AlCl3 are equally strong Lewis acids
D Both BCl3 and AlCl3 are not Lewis acids

The correct answer is:
BCl3 and AlCl3 are both Lewis acids and BCl3 is stronger than AlCl3

Solution:
In BCl3,pπ-pπ back-donation occurs between the vacant 2p-orbital of 'B' and fully-filled 3p-orbital of Cl of a B-Cl bond. This pπ-pπ overlapping is not much effective, because of dissimilar sizes of 2p and 3p-orbitals. But in AlCl3 , pπ-pπ overlapping is more effective, because p-orbitals of Al and Cl belongs to the same energy levels and hence, they are of similar sizes. As a result of back-donation, the electron-deficiency of Al atom gets more compensated as compared with 'B' in BCl3 and therefore, Lewis acid character of AlCl3 is lesser than that of BCl3 .

Topic: Chemistry, p Block Elements (Group 13 & 14), JEE Main
Which of the following statements is correct?

Options:
A The bond length in CO is 1.128 Ã and CO+ is 1.115 Ã because during conversion of CO to CO+, electron is removed from anti bonding orbital
B The bond length in CO is 1.115Â Ã and CO+ is 1.128Â Ã because during conversion of CO to CO+ electron is removed from bonding orbital
C During conversion of CO to CO+ bond length does not vary because bond order remain same
D The bond length in CO is 1.115Â Ã and CO+ is 1.128Â Ã because bond order decreases during conversion of CO to CO+

The correct answer is:
The bond length in CO is 1.128 Ã and CO+ is 1.115 Ã because during conversion of CO to CO+, electron is removed from anti bonding orbital

Solution:
Because of the greater difference in electronegativity between C and O, the energy of the molecular orbitals in CO are in the following order
Ï1s2Ï1s*2 Ï2s2 Ï2py2 =Ï2pz2 Ï2pz 2Ï2s *2
Bond order in CO= 12 10 â 4=3

Topic: Chemistry, Chemical Bonding and Molecular Structure, NEET
Which of the following statements is correct?

Options:
A If the centre of mass is at rest, then the net work done by all the forces acting on the system is zero
B If the velocity of the centre of mass remains zero, then the net external force acting on the system must be zero
C If the speed of centre of mass is changing, then there must be some work done by the internal forces on the system
D If centre of mass of a three-particle system is at rest and it is known that two of the particles are moving in different non-collinear lines, then third particle may be moving

The correct answer is:
If the velocity of the centre of mass remains zero, then the net external force acting on the system must be zero

Solution:
The velocity of the centre of mass changes only if some external force (net external resultant) acts on it. Internal forces do not affect the motion of the centre of mass.

Topic: Physics, Center of Mass Momentum and Collision, NEET
Which of the following Statements is correct?

Options:
A
The rate of radioactive decay cannot be controlled but that of nuclear fission can be controlled.

B
Nuclear forces are short range, attractive and charge dependent.

C
Nuclei of atoms having same number of neutrons are known as isobars.

D
Wavelength of matter waves is given by de Broglie formula but that of photons is not given by the same formula

The correct answer is:
The rate of radioactive decay cannot be controlled but that of nuclear fission can be controlled.

Solution:
Radioactive decay is a continuous process. Rate of radioactive decay cannot be controlled. Nuclear fission can be controlled but not of nuclear fusion.

Topic: Physics, Nuclear Physics, JEE Main, JEE Main 2012 (12 May Online)
Which of the following statements is correct?

Options:
A
RNA controls the synthesis of proteins.

B
The sugar present in DNA is D-(-)-ribose.

C
RNA has double stranded $\alpha$-helix structure.

D
DNA mainly occurs in the cytoplasm of the cell.

The correct answer is:
The sugar present in DNA is D-(-)-ribose.

Solution:
No Solution Available

Topic: Chemistry, Biomolecules, JEE Main, JEE Main 2012 (26 May Online)
Which of the following statements is correct?

Options:
A Gluconic acid can form cyclic (acetal/hemiacetal) structure
B Gluconic acid is a dicarboxylic acid
C Gluconic acid is a partial oxidation product of glucose
D Gluconic acid is obtained by oxidation of glucose with HNO3

The correct answer is:
Gluconic acid is a partial oxidation product of glucose

Solution:
Gluconic acid is obtained by partial oxidation of glucose by tollen’s reagent or fehling solution or Br2/H2O. Gluconic acid can not form hemiacetal or acetal.

Topic: Chemistry, Biomolecules, JEE Main, JEE Main 2020 (07 Jan Shift 2)
Which of the following statements is correct

Options:
A The angular momentum decreases as the particle's velocity increases.
B The angular momentum increases as the particle's velocity decreases.
C the angular momentum about any point of a single particle moving with constant velocity remains constant throughout the motion
D The angular momentum is directly proportional to the particle's potential energy.

The correct answer is:
the angular momentum about any point of a single particle moving with constant velocity remains constant throughout the motion

Solution:
Correct Option is : (C)
the angular momentum about any point of a single particle moving with constant velocity remains constant throughout the motion

Topic: Chemistry, Rotational Motion, NEET
Which of the following statements is correct?

Options:
A Rectification efficiency of a half wave rectifier is equal to that of a full wave rectifier.
B All of the given options
C Rectification efficiency of a half wave rectifier is lower than that of a full wave rectifier.
D Rectification efficiency of a half wave rectifier is higher than that of a full wave rectifier.

The correct answer is:
Rectification efficiency of a half wave rectifier is lower than that of a full wave rectifier.

Solution:
The correct answer is Rectification efficiency of a half wave rectifier is lower than that of a full wave rectifier.
concept:
Comparison between Half-Wave and Full-Wave Rectifier:
$\begin{array}{|l|l|l|}
\hline \text{Parameters} & \text{Half-wave Rectifiers} & \text{Full-wave Rectifiers} \\
\hline \text{Ripple Factor} & 1.21 & 0.482 \\
\hline \text{Transformer Utilization Factor} & 0.286 & 0.573 \\
\hline \text{Voltage Regulation} & \text{Good} & \text{Better} \\
\hline \begin{array}{l}
\text{The fundamental frequency of} \\
\text{the ripple}
\end{array} & \begin{array}{l}
\text{Equal to Supply} \\
\text{Frequency}
\end{array} & \text{Double of Supply Frequency} \\
\hline \text{Peak Inverse Voltage} & Vs & 2 Vs \\
\hline \text{DC Output Voltage} & I \max/m RL & 2 / \pi RL I \max \\
\hline \text{Rectification Efficiency} & 0.406 & 0.812 \text{(double of HW Rectifier)} \\
\hline \text{Form Factor} & 1.57 & 1.11 \\
\hline \text{Peak Factor} & 2 & 1.414 \\
\hline \text{Number of diodes} & \text{Only} 1 & \begin{array}{l}
\text{Vary from } 2 \text{ to } 4,4 \text{ in case of the} \\
\text{bridge rectifier}
\end{array} \\
\hline
\end{array}$

Topic: Physics, Semiconductors, JEE Main
Which of the following statements is correct about a carbonyl group?

Options:
A The carbonyl carbon is sp-hybridised
B The carbonyl carbon is sp3-hybridised
C The three groups attached to the carbonyl carbon lie in the same plane
D The three groups attached to the carbonyl carbon lie in different planes

The correct answer is:
The three groups attached to the carbonyl carbon lie in the same plane

Solution:
In the carbonyl group, carbon atom is in a state of sp2 hybridisation. One sp2 hybrid orbital overlap with a unhydridised p-orbital of oxygen to form C-O σ-bonds. The remaining two sp2 orbitals of carbon form σ-bonds with s-orbitals of hydrogen or sp3-orbitals of carbon of the alkyl groups. The C-O π-bond is formed by the sideways overlap of p-orbitals of carbon and oxygen. Thus, the three σ-bonds of carbonyl carbon lie in one plane and are 120° aprat

Topic: Chemistry, Aldehydes and Ketones, NEET
Which of the following statements is correct for a lyophilic sol?

Options:
A It is not easily solvated
B The coagulation of this sol is irreversible in nature
C It is unstable
D It is quite stable in a solvent

The correct answer is:
It is quite stable in a solvent

Solution:
In lyophilic sols, the dispersed phase particles have great affinity for the dispersion medium. These sols are reversible. These are quite stable. Examples include gum, gelatin, starch, proteins and rubber etc.

Topic: Chemistry, Surface Chemistry, JEE Main
Which of the following statements is correct for any thermodynamic system?

Options:
A
The internal energy changes in all processes.

B
Internal energy and entropy are state functions.

C
The change in entropy can never be zero.

D
The work done in an adiabatic process is always zero.

The correct answer is:
Internal energy and entropy are state functions.

Solution:
No Solution Available

Topic: Physics, Thermodynamics, JEE Main, JEE Main 2004
Which of the following statements is correct for any thermodynamic system

Options:
A The internal energy changes in all processes
B Internal energy and entropy are state functions
C The change in entropy can never be zero
D The work done in an adiabatic process is always zero

The correct answer is:
Internal energy and entropy are state functions

Solution:
The internal energy and entropy depend only on the initial and final states of the system and not on the path followed to attain that state.

Topic: Physics, Thermodynamics, JEE Main
Which of the following statements is correct for covalent bond

Options:
A Electrons are shared between two atoms
B It may be polar or non-polar
C Direction is non-polar
D Valency electrons are attracted

The correct answer is:
It may be polar or non-polar

Solution:
Correct option is 2. It may be polar or non polar
A covalent bond is the same as a ionic bond. The Octet rule only applys to molecules with covalent bonds. A molecule is polar if the shared electrons are equally shared. A molecule is nonpolar if the shared electrons are equally shared

Topic: Chemistry, Chemical Bonding and Molecular Structure, JEE Main
Which of the following statements is correct for electromeric effect?

Options:
A It is a temporary effect.
B It is the property shown by \( \pi \)-bonds.
C It takes place in the presence of a reagent, i.e., an electrophile or a nucleophile.
D All are correct

The correct answer is:
All are correct

Solution:
Electromeric effect is the complete shifting of π electrons present between two atoms in the presence of an attacking reagent. This effect is shown by compounds which have multiple bonds like:C=C, C≡C, N=N, C=O, C≡N etc.

It means π-bond is involved in this effect.

Since this effect takes place in the presence of an attacking reagent, it is a temporary effect. It is of two types i.e., +E and-E .

Topic: Chemistry, General Organic Chemistry, JEE Main
Which of the following statements is correct for optically active alkyl halides, upon reaction with nucleophiles?

Options:
A (a)
B (b)
C (c)
D (d)

The correct answer is:
(b)

Solution:
If an asymmetric carbon atom is not able to retain its spatial arrangement during a chemical reaction is known as inversion. Which occurs during $\mathrm{S}_{\mathrm{N}}$ 2reaction. The nucleophile attacks the $\mathrm{C}-X$ bond of an alkyl halide by the backside and so the configuration of molecule gets inverted.
While in $\mathrm{S}_{\mathrm{N}} 1$ mixture of both the types are obtained and is called racemisation.

Topic: Chemistry, Haloalkanes and Haloarenes, JEE Main
Which of the following statements is correct regarding a solution of two compounds A and $\mathrm{B}$ exhibiting positive deviation from ideal behaviour?

Options:
A Intermolecular attractive forces between $A-A$ and $B-B$ are stronger than those between $A-B$.
B $\Delta_{\text {mix }} H=0$ at constant $T$ and $p$
C $\Delta_{\text {mix }} V=0$ at constant $T$ and $p$
D Intermolecular attractive forces between $A-A$ and $B-B$ are equal to those between $A-B$.

The correct answer is:
Intermolecular attractive forces between $A-A$ and $B-B$ are stronger than those between $A-B$.

Solution:
Solution exhibits positive deviation from ideal behaviour if the intermolecular interactions, i.e., A-B interactions are more stronger than in pure components, i.e. between $\mathrm{A}-\mathrm{B}$ or $\mathrm{B}-\mathrm{B}$. Thus. option (a) is correct. The remaining options are valid only for ideal solutions.

Topic: Chemistry, Solutions, NEET, NEET 2019 (Odisha)
Which of the following statements is correct regarding the photoelectric experiment?

Options:
A The photocurrent increases with intensity of light.
B Stopping potential increases with increase in intensity of incident light.
C The photocurrent increases with increase in frequency.
D All of the above.

The correct answer is:
The photocurrent increases with intensity of light.

Solution:
The photocurrent increases linearly with intensity of the incident light, but is independent of its frequency.
The stopping potential increases linearly with the frequency of the incident light, but is independent of its intensity.

Topic: Physics, Dual Nature of Matter, JEE Main
Which of the following statements is false?

Options:
A Kirchhoff's second law represents energy conservation
B Wheatstone bridge is the most sensitive when all the four resistances are of the same order of magnitude
C In a balanced Wheatstone bridge if the cell and the galvanometer are exchanged, the null point is disturbed
D A rheostat can be used as a potential divider

The correct answer is:
In a balanced Wheatstone bridge if the cell and the galvanometer are exchanged, the null point is disturbed

Solution:
Let us assume R1, R2, R3 & R4 is connected balanced wheat stone bridge, such that R1R3=R2R4 ...1 as shown below,

If galvanometer and cell is exchanged, then circuit becomes as shown in below figure,

The circuit is redrawn and can be visualised as below figure,

In this case, if it is balanced, then there must be,
R1R2=R3R4 ...2
Equation 1 & 2 realises that, both equations are same, which means null point is not affected.

Topic: Physics, Current Electricity, JEE Main, JEE Main 2017 (02 Apr)
Which of the following statements is false?

Options:
A Splitting of spectral lines in electrical field is called Stark effect
B Frequency of emitted radiation from a black body goes from a higher wavelength to lower wavelength as the temperature increases
C Photon has momentum as well as wavelength
D Rydberg constant has unit of energy

The correct answer is:
Rydberg constant has unit of energy

Solution:
Rydberg constant has unit length-1
1λ=Rz2[1n12−1n22] ;  unit  of  R=Length−1 (cm−1)

Topic: Chemistry, Structure of Atom, JEE Main, JEE Main 2018 (16 Apr Online)
Which of the following statements is false?

Options:
A Mg2+ ions form a complex with ATP.
B Ca2+ ions are important in blood clotting.
C Ca2+ ions are not important in maintaining the regular beating of the heart.
D Mg2+ ions are important in the green parts of plants.

The correct answer is:
Ca2+ ions are not important in maintaining the regular beating of the heart.

Solution:
Monovalent sodium and potassium ions and divalent magnesium and calcium ions are found in large properties in biological fluids. There ions perform important biological functions such as maintenance of heart and nerve impulse. So, Ca2+ ions are important in maintaining the regular beating of the heart.

Topic: Chemistry, s Block Elements, NEET, NEET 2016 (Phase 1)
Which of the following statements is false for a particle moving in a circle with a constant angular speed?

Options:
A
The velocity vector is tangent to the circle.

B
The acceleration vector is tangent to the circle.

C
The acceleration vector points to the centre of the circle.

D
The velocity and acceleration vectors are perpendicular to each other.

The correct answer is:
The acceleration vector is tangent to the circle.

Solution:
The acceleration vector is along the radius of circle.

Topic: Physics, Work Power Energy, JEE Main, JEE Main 2004
Which of the following statements is false for a particle moving in a circle with a constant angular speed?

Options:
A
The velocity vector is tangent to the circle.

B
The acceleration vector is tangent to the circle.

C
The acceleration vector points to the centre of the circle.

D
The velocity and acceleration vectors are perpendicular to each other.

The correct answer is:
The acceleration vector is tangent to the circle.

Solution:
The acceleration vector is along the radius of circle.

Topic: Physics, Work Power Energy, JEE Main
Which of the following statements is false regarding SDS-polyacrylamide gel electrophoresis?

Options:
A Proteins are separated by molecular weight
B SDS is a detergent which gives charge to protein
C Large protein move more slowly through gel
D SDS is used to maintain the 3-dimentional structure of protein

The correct answer is:
SDS is used to maintain the 3-dimentional structure of protein

Solution:
For protein SDS (Sodium Dodecyl Sulphate) is an anionic detergent applied to protein sample linearize proteins and to impart a negative charge to linearzed proteins.

Topic: Biology, Biotechnology - Principles and Processes, JIPMER, JIPMER 2015
Which of the following statements is false when p is true and q is false?

Options:
A p⇒qâr
B pâq⇒r
C q⇒r⇒p
D râpâq

The correct answer is:
r⇒p⇒q

Solution:
p	q	r	p⇒q⇔r	p⇔q⇒r	q⇒r⇒p	r⇒p⇒q

T	F	T	F	T	T	F

T	F	F	T	T	T	F

Topic: Mathematics, Mathematical Reasoning, JEE Main
Which of the following statements is incorrect?

Options:
A In Hall-Heroult process, the electrolyte used is a molten mixture of alumina, sodium hydroxide and cryolite.
B Lead is extracted form its chief ore by both carbon reduction and self reduction.
C Tin is extracted from its chief ore by carbon monoxide reduction.
D Siderite and cassiterite are carbonate ores.

The correct answer is:
Siderite and cassiterite are carbonate ores.

Solution:
(i) Molten mixture of alumina and cryolite
(ii) 2PbS+3O2→2Pb+2SO2 (self-reduction)
PbS+2PbO→3Pb+SO2 (Self reduction)
PbO+C→Pb+CO (carbon reduction)
(iii) SnO2+C→Sn+CO (carbon reduction
(iv) siderite =FeCO3 , cassiterite =SnO2 and argentite =Ag2S.

Topic: Chemistry, General Principles and Processes of Isolation of Metals, JEE Main
Which of the following statements is incorrect?

Options:
A Calamine and siderite are carbonates
B Argentite and cuprite are oxides
C Zinc blende and pyrites are sulphides.
D Malachite and azurite are ores of copper

The correct answer is:
Argentite and cuprite are oxides

Solution:
A Calamine =ZnCO3 , Sidereite =FeCO3
B Argentite =Ag2S and Cuprite =Cu2O
C Zinc blende =ZnS , Pyrites =FeS2
D Malachite =CuCO3CuOH2 , Azurite =2CuCO3CuOH2

Topic: Chemistry, General Principles and Processes of Isolation of Metals, JEE Main