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: A student pushes a box to slide it across the floor. Which statement explains why the box begins to move?  
 (A) The weight of the box is greater than the force of friction. (B) The weight of the box is less than the force of friction. (C) The applied force is greater than the force of friction. (D) The applied force is less than the force of friction.

A: C
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Q: The cheetah population around the world has decreased because of poaching and loss of habitat. The surviving population is found to have similar alleles. Which factor is endangering the species' survival the most?  
 (A) harmful genetic mutations (B) shrinking of the gene pool (C) decrease in competition (D) increase in adaptations

A: B
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Q: Which of these best describes the relationship between Earth's layers?  
 (A) The hottest layers are closest to the core. (B) The more liquid layers are closest to the crust. (C) The lightest layers are closest to the core. (D) The more metallic layers are closest to the crust.

A:
A
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