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").

[EX Q]: Fact1: Ants communicate with chemicals called pheromones., Fact2: Ants are of extreme importance in the insect world., Question: How do some insects communicate? (A) sound (B) sensory neurons (C) Decibels (D) electronic waves (E) progesterone (F) Vibrates (G) pheromones (H) radio waves
[EX A]: G

[EX Q]: Fact1: water causes refraction of light, Fact2: Halos are produced by the refraction of light., Question: What causes halos? (A) germs (B) Pacific (C) solutes (D) water (E) storms (F) glass (G) algae (H) the sun
[EX A]: D

[EX Q]: Fact1: some animals' fur grows thicker for staying warm in the winter, Fact2: Winter is snow, winter is Christmas., Question: Why do some animals grow thicker fur around Christmas in the Northern hemisphere? (A) overheat (B) protect them (C) stay warm (D) climate (E) adding heat (F) warm other animals (G) stay cool (H) sun's heat
[EX A]:
C