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.
--------
Question: Animals get energy for growth and repair from  
 (A) soil (B) food (C) water (D) air

Answer: B


Question: What type of galaxy is the Milky Way?  
 (A) spiral (B) elliptical (C) irregular (D) oval

Answer: A


Question: Why do trees like oaks and walnuts depend upon squirrels?  
 (A) to control population size (B) to pollinate their flowers (C) to remove dead wood (D) to aid in seed distribution

Answer:
D