You are given a science question (hard-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.

Input: Consider Input: Which animal is preparing for a seasonal change in the environment?  
 (A) a bat flying at night (B) a deer drinking water (C) an owl eating a mouse (D) a squirrel storing nuts

Output: D


Input: Consider Input: A main function of a plant's seed is to  
 (A) store food to be used during early development (B) attract pollen to be used during development (C) take in light energy to be used during photosynthesis (D) produce chlorophyll to be used during photosynthesis

Output: A


Input: Consider Input: In which way are rainforests and coral reefs different from ecosystems with few species?  
 (A) There are more prey than predators. (B) The food web is more stable and lasting. (C) Organisms often must compete for food. (D) Plant populations are the primary producers.


Output: B