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: tidal energy can be used to produce electricity, Fact2: Tidal caves are formed by the energy of the rising and falling tides., Question: what can produce electricity? (A) rivers (B) animal transport (C) tidal caves (D) Nematoda (E) rays or beams (F) animals (G) cactuses (H) photons

A: C
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Q: Fact1: Biodiversity increases the productivity and stability of ecosystems., Fact2: An ecosystem includes the organisms and their habitat., Question: what does biodiversity increase the productivity and stability of? (A) density (B) the looseness of soil (C) water vapor (D) the environment (E) h2o (F) swamp vegetation (G) biological diversity (H) organisms and their habitat

A: H
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Q: Fact1: Flagella help prokaryotes move., Fact2: Flagella are long filaments made up of the protein flagellin., Question: What moves with long filaments? (A) prokaryotes (B) sponges (C) an object (D) lizards (E) protein (F) sensory neurons (G) insects (H) Most plants

A:
A
****