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 student wants to look under a heavy rock. Which simple machine would be BEST to use to lift the rock?  (A) Wheel and axle (B) Lever (C) Inclined plane (D) Scre?

A: B.
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Q: Question: When an octopus feels threatened, it can release black ink into the water. The ink MOST likely helps the octopus  (A) move quickly through the water. (B) breathe oxygen from the water. (C) hide from predators. (D) use food faster?

A: C.
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Q: Question: Elephant's long trunks enable them to  (A) reach food and water (B) breathe (C) move quickly (D) fight predator?

A:
A.
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