You are given a science question (hard-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.

Example Input: Where does evaporation occur at the HIGHEST rate?  
 (A) rivers (B) streams (C) estuaries (D) glaciers
Example Output: C

Example Input: Growth and activities of organisms can speed up the chemical weathering of rocks. Which organisms naturally cause most of the chemical weathering of rocks?  
 (A) small mammals (B) plant seedlings (C) mosses (D) insects
Example Output: C

Example Input: Which adaptation often helps an animal attract a mate?  
 (A) hibernation (B) camouflage (C) coloration (D) migration
Example Output:
C