In this task, you are given two facts, and a multiple-choice question. Based on the given facts, answer the question with index of the correct option (e.g, "A").

Q: Fact1: matter vibrating can cause sound, Fact2: All matter emits vibrations., Question: What kind of matter can produce sound? (A) sensory neurons (B) all matter (C) an object (D) only liquids (E) mechanical (F) only plasma (G) only solids (H) waves

A: B
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Q: Fact1: All chemical reactions require activation energy to get started., Fact2: Fire is a chemical reaction., Question: What does fire require to get started? (A) an engine (B) activation energy (C) water (D) energy usage (E) direct energy (F) dogs (G) activated almonds (H) adding heat

A: B
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Q: Fact1: Reproduction is the process by which organisms give rise to offspring., Fact2: Mutations are sources of variations in offspring., Question: What can happen during the reproduction process? (A) tree falls (B) Mutations (C) Plants growth (D) movement (E) competition (F) adding heat (G) contamination (H) Dehydration

A:
B
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