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").
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Question: Fact1: Caffeine is a central nervous system stimulant., Fact2: Cocaine is a stimulant and increases the user's heart rate and blood pressure., Question: What does caffeine do? (A) Increase fame (B) increases a body's strength (C) Release energy (D) Increase user's heart rate (E) Transfers energy (F) decrease stamina (G) Increase intelligence (H) Increase wealth

Answer: D

Question: Fact1: Veins generally carry deoxygenated blood., Fact2: Arteries and veins are blood vessels., Question: what generally carries deoxygenated blood? (A) blood vessels (B) animals (C) layers of fat (D) mammals (E) critical organs (F) an organism's body (G) elephants (H) athletes

Answer: A

Question: Fact1: Cells secrete acids and bases to maintain the proper pH for enzymes to work., Fact2: Most human enzymes work at a optimal pH of 7.4, but other enzymes work at many different pH ranges., Question: Cells secrete acids and bases to maintain what? (A) Chemical energy (B) resistance (C) increases a body's strength (D) To keep their body heat. (E) most human enzymes (F) aerobic capacity (G) allow growth (H) temperature

Answer:
E