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: What are produced in both the male and female reproductive systems in humans?  
 (A) sperm (B) nutrients (C) fertilized eggs (D) sex cells

A: D
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Q: A pot is heated on a stove. Which process causes the metal handle of the pot to also become hot?  
 (A) combustion (B) convection (C) radiation (D) conduction

A: D
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Q: A push or a pull on an object is an example of  
 (A) force. (B) weight. (C) energy. (D) work.

A:
A
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