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.

Example Input: What is the function of the nucleus in a cell?  
 (A) provides energy (B) provides nutrients (C) controls activity (D) controls movement
Example Output: C

Example Input: Kim lost her hammer outside. When she found it a few months later, some parts of the metal were covered with flaky, brown rust. Which type of change occurred when rust formed on the hammer?  
 (A) chemical (B) electrical (C) thermal (D) physical
Example Output: A

Example Input: The Piedmont and Coastal Plains regions in Maryland produce crops such as corn, soybeans, wheat, tobacco, tomatoes, and apples. Which environmental factor most likely influences which crops are grown in these regions?  
 (A) soil quality (B) wind speeds (C) bird migration (D) water temperature
Example Output:
A