TASK DEFINITION: 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.
PROBLEM: 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

SOLUTION: A

PROBLEM: Which of these technologies helps a power company use renewable energy for the production of electricity?  
 (A) hydroelectric power (B) nuclear power plants (C) natural gas generators (D) coal-fired power plants

SOLUTION: A

PROBLEM: When manned space exploration began, NASA used the gravity assist concept so that spacecraft could conserve fuel. Which statement explains why the gravity assist concept was useful for spacecraft to successfully travel and return to Earth?  
 (A) It gave spacecraft a timed trajectory. (B) It ensured spacecraft would return home safely. (C) It was helpful in planning spacecraft trajectories. (D) It ensured spacecraft would avoid being pulled into the sun.

SOLUTION:
C