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: What do *** use as *** for ***?  (A) carbon dioxide (B) oxygen (C) minerals (D) nitroge.

Answer: E.


Question: Question: Clouds bring rain and snow to Earth's surface. How do rain and snow most support *** on Earth?  (A) They cool the land surface. (B) They carry acids into the soil. (C) They bring freshwater to land organisms. (D) They build up mountains.

Answer: C.


Question: Question: Which *** is the best *** of ***?  (A) metal fork (B) rubber boot (C) plastic spoon (D) wooden bat.

Answer:
E.