Given a scientific question, generate an incorrect answer to the given question. The incorrect answer should be a plausible alternative to the correct answer. The answer should be some other item belonging to the same category as the correct answer but should be incorrect.

Q: Nitrogen is an important macronutrient because it is part of nucleic acids and proteins. atmospheric nitrogen, which is the diatomic molecule n2, or dinitrogen, is the largest pool of nitrogen in these?

A: gas planets
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Q: Each pollen grain has two coverings: the exine (thicker, outer layer) and the what?

A: tube nucleus
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Q: Hemoglobin, with four polypeptide chains or subunits, is the most frequently cited example of a protein having what kind of structure?

A:
binary
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