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 bird is about to lay an egg, so it needs to construct a safe, round place to place the egg in. The bird constructs using (A) sticks (B) gum (C) rocks (D) tape

A: A
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Q: A plant needs to use the roots of itself to move essential things (A) to the dirt (B) to the sky (C) to the plasma (D) to the buds

A:
D
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