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.

Input: Consider Input: How many elements are in the compound Mg(OH)2?   
 (A) 2 (B) 3 (C) 4 (D) 5

Output: B


Input: Consider Input: A student reads the following description of a region: "It has warm summers, moderate winters, and frequent rainfall." What information does this description best provide?  
 (A) current weather (B) weather forecast (C) general climate (D) climate changes

Output: C


Input: Consider Input: Which of these processes makes it possible for cells to take in water?  
 (A) osmosis (B) mitosis (C) photosynthesis (D) respiration


Output: A


