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'.

Q: Question: *** *** *** following items *** *** wrecking yard operates *** *** help *** *** electromagnet?  (A) dump truck (B) crane to pick up, haul, and drop cars (C) fence that surrounds the wrecking yard (D) dumpster for leftover part.

A: B.
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Q: Question: We are able to see the moon in the sky because the  (A) moon is only visible at night. (B) Earth's light is reflected off of the moon. (C) moon gives off light. (D) sun's light is reflected off of the moon.

A: D.
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Q: Question: *** object *** *** best conductor *** electricity?  (A) metal fork (B) rubber boot (C) plastic spoon (D) wooden bat.

A:
A.
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