You are given a science question (easy-level) and four answer options (associated with "A", "B", "C", "D"). Your task is to find the correct answer based on scientific facts, knowledge, and reasoning. Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D'. There is only one correct answer for each question.

Q: Which describes a material that is not a food?  
 (A) It stores energy but not nutrients. (B) It does not store energy or nutrients. (C) It stores energy and nutrients. (D) It does not store energy but stores nutrients.

A: B
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Q: The number of fish in a lake suddenly increases. How will the increase most likely affect the lake?  
 (A) There will be less water in the lake. (B) More plants will grow in the lake. (C) More frogs will live in the lake. (D) There will be fewer insects in the lake.

A: D
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Q: Mount Arenal, a volcano in Costa Rica, is erupting. Heat is being released during the eruption. What is the source of the heat?  
 (A) The heat comes from the Sun. (B) The heat comes from pools of underground water. (C) The heat comes from deep within Earth. (D) The heat comes from decaying plants and animals.

A:
C
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