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:
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:
The pull of gravity from Earth has the greatest effect on  
 (A) comets. (B) the Sun. (C) asteroids. (D) the Moon.

Ex Output:
D


Ex Input:
What type of inheritance controls blood types in humans?  
 (A) incomplete dominance (B) polygenic inheritance (C) multiple alleles (D) recessive genes

Ex Output:

C