In this task, you need to answer basic science questions. For each question, several terms are intentionally masked with ***. This masking can cover very few or many of the question words. Clearly, if masked terms are important, the modified question will be impossible to answer. Please indicate the correct answer with one of the following responses: "A", "B", "C", "D" or "E". While "A"-"D" correspond to the answer options provided in the input, "E" represents "I don't know" for questions that do not provide enough information. Respond via "E" if the question is not answerable. Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D', 'E'.
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Question: Question: *** is learning about *** ***s of ***. Which is an *** of a *** ***?  (A) webbed feet on a duck (B) migration of songbirds (C) sharp eyesight of an eagle (D) camouflaged colors on a fro.

Answer: E.


Question: Question: A scientist put several different *** in a sealed container. Every hour, she checked the *** in the *** to see if it ***d. How did the *** in the *** most likely ***?  (A) The amount of oxygen increased. (B) The amount of oxygen decreased. (C) The oxygen was transformed into water. (D) The oxygen was transformed into carbon dioxide.

Answer: E.


Question: Question: Timber companies can best *** the number of *** in *** by  (A) converting deforested areas into malls. (B) planting trees to replace what they cut down. (C) adding pesticides to the soil around the trees. (D) removing the tree stumps when trees are cut down.

Answer:
B.