In this task, you are given a question and answer options for that question. Using this information, you have to classify each text into different topics: medicine, nursery, psychology, chemistry, pharmacology, biology.
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Question: Question: The main vessels that regulate blood flow are: 
 Options:  <0> Arteries <1> Arterioles <2> Capillaries <3> Venules <4> Veins.

Answer: biology


Question: Question: The reaction of 1H-indole with electrophiles takes place selectively on the atom in position: 
 Options:  <0> one. <1> two. <2> 3. <3> Four. <4> 5.

Answer: chemistry


Question: Question: Of the following statements of the electron transport chain. Which is true ?: 
 Options:  <0> An FADH molecule can generate up to 2.5 molecules of ATP. <1> One molecule of NADH can generate up to 1.5 molecules of ATP. <2> Electrons flow from more positive reduction potentials to more negative reduction potentials. <3> Complex II (used by FADH2) does not transfer protons to the intermembrane space. <4> Complex III uses copper (Cu) atoms as cofactors.

Answer:
chemistry