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").

Example Input: 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
Example Output: G

Example Input: Fact1: Migrants typically travel long distances., Fact2: Migrant birds arrive., Question: What travels long distances? (A) humans (B) jets (C) rocks (D) birds (E) camels (F) cocoons (G) Light (H) eggs
Example Output: D

Example Input: Fact1: a measuring cup is used for measuring the volume of substances, Fact2: With a measuring cup, pour different amounts of water into each cup., Question: What can determine the amount of water? (A) rainfall (B) streams. (C) the volume (D) streams (E) evaporation (F) Temperature (G) erosion (H) vaporization
Example Output:
C