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: nuclear reactions in stars causes stars to produce light, Fact2: And, of course, the Sun is a star., Question: What in the sun causes the sun to produce light? (A) energy of moving objects (B) hydrogen and oxygen (C) heat energy (D) water (E) solar rays (F) rotation (G) nuclear reactions (H) kinetic energy
[EX A]: G

[EX Q]: Fact1: Evolution is a change in the characteristics of living things over time., Fact2: Trees are the largest of living things., Question: Evolution changes the characteristics of what over time? (A) the Moon (B) Man (C) life (D) trees (E) rocks (F) the Sun (G) humans (H) plants
[EX A]: D

[EX Q]: Fact1: Organisms cluster around hydrothermal vents in the ocean floor., Fact2: Largest of the oceans on Earth is the Pacific Ocean ., Question: what floor do organisms cluster around hydrothermal vents on? (A) Pacific (B) small ponds (C) ground (D) limestone (E) sandstone (F) loose soil (G) atmosphere (H) crust
[EX A]:
A