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: soil is formed by rocks eroding, Fact2: Rivers erode the rocks they flow over., Question: What is formed by rivers? (A) fish (B) soil (C) rain (D) bamboo (E) spring (F) clouds (G) kayaks (H) NaCl

A: B
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Q: Fact1: Plasma cells are activated B cells that secrete antibodies., Fact2: Antibodies are produced by plasma cells., Question: antibodies are produced by activated B cells that do what? (A) Animal survival (B) killing insects (C) interact (D) secrete them (E) migrate (F) reproduce (G) competition (H) Allergies

A: D
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Q: Fact1: smell is used for finding food by some animals, Fact2: Olfaction is the sense of smell., Question: What does olification help some animals when they are hungry in the wild? (A) lysing (B) seeds (C) a mate (D) immune (E) food (F) Energy (G) friends (H) a place to live

A:
E
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