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: All of the planets in the solar system formed at about the same time from a large cloud of gas and dust. How is Earth different from other planets in the solar system?  
 (A) Earth has no natural satellites. (B) Earth's atmosphere is composed of gases. (C) Water is found in all three phases on Earth. (D) Volcanoes release liquid rock onto Earth's surface.

A: C
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Q: Some people carry a mutated allele of a particular gene that makes them resistant to HIV infection and AIDS. Which best describes this type of mutation?  
 (A) beneficial (B) asexual (C) harmful (D) unicellular

A: A
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Q: Evidence suggests that there is a relationship between ancient dinosaurs and modern birds. Through time, each occurrence of a new trait most likely resulted from which of the following?  
 (A) mutation of genes (B) hybridization of species (C) extinction of populations (D) alteration of the environment

A:
A
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