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.

Q: Which of the following is the most likely cause of earthquakes?  
 (A) shifting rock layers (B) crashing meteorites (C) rotation of the core (D) magnetic force

A: A
****
Q: When microorganisms deplete the oxygen in soil through respiration, the soil becomes  
 (A) humus. (B) anaerobic. (C) compost. (D) aerobic.

A: B
****
Q: Ospreys are birds that eat fish. Where would an osprey most likely live?  
 (A) near a forest (B) near a marsh (C) near a desert (D) near a prairie

A:
B
****