You are given a science question (easy-level) and four answer options (associated with "A", "B", "C", "D"). Your task is to find the correct answer based on scientific facts, knowledge, and reasoning. Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D'. There is only one correct answer for each question.

[EX Q]: A star is a large astronomical body that
(A) reflects light. (B) condenses light. (C) emits light. (D) absorbs light.
[EX A]: C

[EX Q]: What is the downward movement of water through pores and other spaces in soil due to the force of gravity?
(A) percolation (B) evaporation (C) precipitation (D) condensation
[EX A]: A

[EX Q]: Large amounts of industrial gases are released into the atmosphere every day. What happens to those gases?
(A) They are broken down by ultraviolet light from the Sun. (B) They are converted into nitrogen and oxygen. (C) They rise through the atmosphere and go into outer space. (D) They remain in the atmosphere for long periods of time.
[EX A]:
D