Logic of a solution: *Air pollution harms the respiratory and circulatory systems. Sulfur dioxide can irritate the respiratory system and damage the heart and circulatory system. Air pollution damages the heart.*
*(C)*
The original question: *What organ is harmed by air pollution?
Options:
- (A) piano
- (B) church organ
- (C) heart
- (D) harp
- (E) bushes
- (F) animals
- (G) eardrum
- (H) lungs*

Line 1: *Most people can survive only a few days without water. Water is everywhere H20. Most people can survive only a few days without H20.*
*(D)*
Line 2: *Most people can survive only a few days without what?
Options:
- (A) carbon dioxide
- (B) oxygen
- (C) h2o
- (D) H20
- (E) NaCl
- (F) CO2
- (G) soda
- (H) urea*

Logic of a solution: *Molecules of tRNA bring amino acids to the ribosome in the correct sequence. Amino Acids Amino acids are the building blocks of proteins. Molecules of tRNA bring the building blocks of proteins to the ribosome in the correct sequence.*
*(G)*
The original question: *Molecules of _ bring the building blocks of protein to the ribosomes in the correct sequence.
Options:
- (A) form
- (B) fusion
- (C) core
- (D) shape
- (E) sugar
- (F) HIV
- (G) tRNA
- (H) small*

Line 1: *Nephrons are the structural and functional units of the kidneys. Blood is filtered in the kidney. Nephrons are the structural and functional units of the organ that filters blood.*
*(G)*
Line 2: *Nephrons are the structural and functional units of the organ that filters what?
Options:
- (A) Light
- (B) Energy
- (C) Coffee
- (D) liquid
- (E) Air
- (F) Oxygen
- (G) Blood
- (H) Food*

Logic of a solution: *Trees have woody stems covered with bark. During the stripping, the protective layer of inner bark is removed. Trees have woody stems covered with a protective layer.*
*(D)*
The original question: *Trees have woody stems covered with what?
Options:
- (A) food and shelter
- (B) smooth ridges
- (C) looseness
- (D) protective layer
- (E) Organic compounds
- (F) plastic sheet
- (G) heat energy
- (H) thin metal*

Logic of a solution: *Amphibians have sense organs to smell and taste chemicals. Lizards use their tongues as sense organs. Lizards are able to use their tongues to taste.*
*(A)*
The original question:
*What are lizards able to use their tongues to do?
Options:
- (A) taste
- (B) arrange their nest
- (C) noise
- (D) measure prey length
- (E) smell the color of organs
- (F) snort
- (G) breathe
- (H) vibrate*