Detailed Instructions: 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: the gravitational pull of the Moon on Earth 's oceans causes the tides, Fact2: High tide is when the best waves come in., Question: What does the gravitational pull of the Moon on Earth 's oceans cause? (A) Energy. (B) two (C) waves (D) fires (E) the Sun (F) sunlight (G) rivers (H) erosion
A:
C