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:
A condition in bees called "colony collapse disorder" occurs when worker bees leave the hive to collect nectar and never return. How would a decline in the bee population most likely affect a farm ecosystem?  
 (A) There would be a decrease in soil thickness. (B) There would be a decline in fruit production. (C) There would be an increase in plant diseases. (D) There would be an increase in insect pest populations.

Ex Output:
B


Ex Input:
Martin is writing a report for science class about how the tilt of Earth affects living organisms. Which subject should Martin include in his report that is directly affected by Earth's tilt?  
 (A) night and day (B) cloud formation (C) phases of the Moon (D) changing of the seasons

Ex Output:
D


Ex Input:
Plants are producers because they  
 (A) make their own food (B) can grow in soil (C) need water to grow (D) take in nutrients

Ex Output:

A