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 Input:
Which energy source is considered nonrenewable?
(A) moving water (B) fossil fuel (C) wind (D) biomass

Ex Output:
B

Ex Input:
Organisms contribute to the water cycle mainly through the process of
(A) irrigation. (B) evaporation. (C) precipitation. (D) transpiration.

Ex Output:
D

Ex Input:
A student put 200 milliliters (mL) of water into a pot, sets the pot on a burner, and heats the water to boil. When the pot is taken off the burner, it contains only 180 milliliters (mL) of water. What happened to the rest of the water?
(A) It was used up. (B) It condensed. (C) It was absorbed by the heat. (D) It turned into water vapor.

Ex Output:
D