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 particle type can be identified as being from a specific element?  
 (A) electron (B) atom (C) neutron (D) proton

A: B
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Q: A model of the Moon would be different from a model of Earth in that the Moon should  
 (A) be smaller than Earth. (B) have a source of light inside. (C) have a smoother surface than Earth. (D) have fewer impact craters on the surface.

A: A
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Q: When a prairie ecosystem was disturbed, an invasive grass species outcompeted the native grass. The new grass had less nutritional value for the organisms living in the area. Which category of organism will be affected by this change first?  
 (A) predators (B) herbivores (C) scavengers (D) decomposers

A:
B
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