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: heating salt water causes the water to evaporate while the salt remains, Fact2: Flash evaporators are used to make fresh water from salt water., Question: Doing what to salt water causes the water to become fresh water? (A) watershred (B) freezing (C) Regrows it (D) migrate (E) pouring (F) heating (G) cooling (H) erosion
[EX A]: F

[EX Q]: Fact1: Many corals secrete an exoskeleton that builds up to become a coral reef., Fact2: Good examples are Bubble coral, Elegance coral, Frogspawn and other Euphyllia corals., Question: What is secreted by organisms like frogspawn to become a reef? (A) exocrine glands (B) food and shelter (C) exoskeleton (D) bones (E) Energy (F) Chemical energy (G) plasma (H) Energy.
[EX A]: C

[EX Q]: Fact1: Echinoderms use pheromones to communicate with each other., Fact2: Echinoderms are represented by the starfish., Question: How do starfish communicate with each other? (A) huddle together (B) writing (C) during the day (D) pheromones (E) Chemical energy (F) waving their arms (G) Decibels (H) talking
[EX A]:
D