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").
Input: Fact1: knowledge of the stars can be used to navigate, Fact2: Explorers have used the North Star for navigational purposes for centuries., Question: What can be used to find your way if you're lost in the dark? (A) lamphreys (B) Ultraviolet shielding (C) Light shining into it (D) the speed of hearing (E) The north star (F) How to check the temperature (G) Observing tidal waves (H) osculum
Output:
E