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:
Sickle cell anemia is a genetic disease caused by an autosomal recessive gene. If each parent carries one sickle cell allele, what are the chances that their child will have sickle cell anemia?  
 (A) no chance (B) one in four (C) two in four (D) three in four

Ex Output:
B


Ex Input:
A red flowered plant (RR) is crossed with a white flowered plant (WW) and produces plants with pink flowers (RW). If two pink flowered plants are crossed, what color offspring could be produced?  
 (A) red, white, and pink (B) red and white (C) pink and red (D) pink and white

Ex Output:
A


Ex Input:
The difference between the atomic number of an element and the element's atomic mass is the number of  
 (A) ions. (B) protons. (C) electrons. (D) neutrons.

Ex Output:

D