In this subtask, you will answer a simple science question. Please indicate the correct answer. If you're not sure about the answer, choose the last option "I don't know". Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D', 'E'. The "A"-"D" responses correspond to the answer options mentioned in the input. There is a 5th option "E" which should be used for questions for which you're not sure about the answer (e.g., when the questions do not provide enough information to answer).

Q: Question: A simple machine that helps move a flag up a flagpole is  (A) a bar magnet (B) an inclined plane (C) a pulley (D) a leve?

A: C.
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Q: Question: Which of the following is an example of a chemical change?  (A) clouds forming (B) sugar dissolving (C) water freezing (D) a candle burnin?

A: D.
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Q: Question: When can producers make the most food?  (A) summer, because there is more sunlight (B) summer, because there is more heat (C) spring, because there is more rain (D) spring, because there are more leave?

A:
A.
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