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:
Fertilizers added by farmers to the soil contain high amounts of nitrates. How do fertilizers affect the nitrogen cycle?  
 (A) More nitrates are available for plants to absorb. (B) More nitrates are available for animals to eat. (C) More nitrogen gas is released into the atmosphere. (D) More nitrogen is converted by bacteria into nitrates.

Ex Output:
A


Ex Input:
Which of the following statements best explains why earthquakes occur more frequently in California than in Massachusetts?  
 (A) The rock found in California is igneous, but the rock found in Massachusetts is sedimentary. (B) California is located on the boundary of two crustal plates, but Massachusetts is not. (C) The rock under California is soft, but the rock under Massachusetts is hard. (D) California is located on a continental plate, but Massachusetts is not.

Ex Output:
B


Ex Input:
What types of cells are found only in organisms that reproduce sexually?  
 (A) blood cells (B) neurons (C) skin cells (D) gametes

Ex Output:

D