In this task, you are given a multiple-choice question and you have to pick the correct option. Answer with option indexes (i.e., "A", "B", "C", and "D").

Q: When cutting down rain forests, it is important to keep in mind air quality. When too many trees are cut down in a given area, there may be decrease in the air's (A) quality (B) carbon dioxide (C) helium amounts (D) carbin dioyide levels

A: A
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Q: A plant's roots break down rocks as the roots do what? (A) decay (B) grow old (C) develop (D) dcerease

A: C
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Q: Which is true? (A) the equator has winter and summer at the same time (B) humans on the equator celebrate Christmas in May (C) the equator is always cold (D) humans on the equator can go either north or south to change season

A:
D
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