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:
When sodium hydroxide reacts with a copper nitrate solution, the reaction vessel needs to be kept on ice to slow down the reaction. What best describes this reaction?  
 (A) an exothermic reaction that absorbs energy (B) an exothermic reaction that releases energy (C) an endothermic reaction that absorbs energy (D) an endothermic reaction that releases energy

Ex Output:
B


Ex Input:
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 Output:
C


Ex Input:
Volcanoes are considered constructive because they  
 (A) deposit lava. (B) cause erosion. (C) trigger earthquakes. (D) release gases.

Ex Output:

A