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]: Which action does a kitten learn from its mother?  
 (A) how to grow (B) how to meow (C) how to hunt mice (D) how to nurse milk
[EX A]: C

[EX Q]: Which of these best describes wind energy?  
 (A) limited (B) renewable (C) damaging (D) inexpensive
[EX A]: B

[EX Q]: Which human activity contributes to the formation of acid rain?  
 (A) using too much fertilizer in agriculture (B) cutting down large areas of tropical forests (C) burning fossil fuels such as coal and gasoline (D) using chemicals that destroy ozone in the stratosphere
[EX A]:
C