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: *** *** *** when they *** their own ***. Which *** of *** is *** by *** for making ***?  (A) electrical (B) heat (C) light (D) mechanica.

A: E.
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Q: Question: John was using his *** *** when it suddenly *** ***. What is the first thing John should do to try *** the ***?  (A) recharge the battery (B) take the player apart (C) replace the player with a new one (D) change to a different son.

A: E.
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Q: Question: Which *** is a *** *** of ***?  (A) insulates heat (B) conducts electricity (C) strong magnetic force (D) liquid at room temperatur.

A:
E.
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