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 organ is the site of gas exchange between the body and the environment?  
 (A) spleen (B) liver (C) lungs (D) pancreas

A: C
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Q: Which two things interact most in the water cycle?  
 (A) oceans and the Moon (B) oceans and the Sun (C) lakes and the Moon (D) lakes and the Sun

A: B
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Q: The most significant human-induced impact on Earth's atmosphere comes from the use of which energy resource?  
 (A) flowing water (B) fossil fuels (C) sunlight (D) winds

A:
B
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