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: Sweat wets the skin, and when it evaporates, it cools the body., Fact2: Sweat is released from sweat glands beneath the skin, and as it evaporates, the skin is cooled., Question: What cools the skin? (A) humidity (B) temperature (C) condensation (D) Solar energy (E) evaporation (F) vaporization (G) layers of fat (H) water vapor
[EX A]: E

[EX Q]: Fact1: melting is when solids are heated above their melting point, Fact2: Ice cubes melt in liquid water., Question: What, when heated, turns into liquid water? (A) gasoline (B) oil (C) a solute (D) fire (E) ice cubes (F) a prism (G) mussels (H) Energy.
[EX A]: E

[EX Q]: Fact1: Active immunity results when an immune response to a pathogen produces memory cells., Fact2: Memory cells persist in the circulation for decades., Question: what can persist in the circulation for decades? (A) active immunity (B) density (C) Veins and arteries. (D) oxygen cells (E) bacteria (F) chlorofluorocarbons (G) fur and fat (H) Chemical energy
[EX A]:
A