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:
In what type of rock would a geologist most likely find evidence of ancient life?  
 (A) sedimentary (B) foliated (C) metamorphic (D) volcanic

Ex Output:
A


Ex Input:
Which human organ system eliminates liquid and gaseous wastes from the body?  
 (A) circulatory (B) endocrine (C) excretory (D) reproductive

Ex Output:
C


Ex Input:
Which temperature is the freezing point of water?  
 (A) 0°F (B) 32°F (C) 50°F (D) 100°F

Ex Output:

B