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: Four objects are on a wooden ramp. Which object is most likely to roll off the ramp if it is pushed gently?  
 (A) flat eraser (B) round ball (C) bent paper clip (D) wooden cube
Example Output: B

Example Input: A student walking quickly while carrying an orange on his lunch tray stops suddenly. The orange will most likely roll off the tray due to  
 (A) inertia of the orange. (B) centripetal force of the orange. (C) the friction acting on the orange. (D) the balanced forces acting on the orange.
Example Output: A

Example Input: Most hormones are produced by which human organ system?  
 (A) digestive (B) endocrine (C) respiratory (D) nervous
Example Output:
B