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").
Problem:Fact1: knowledge of the stars can be used to navigate, Fact2: Of course, astronomers also study stars., Question: What can be used to navigate? (A) music (B) backbones (C) astrology (D) cilia (E) magic (F) sponges (G) astronomy (H) lamphreys
Solution:
G