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: A leaf is covered in mud during a landslide. After one million years, this leaf will most likely be ___.
(A) a fossil (B) an animal species (C) a new plant species (D) a nonrenewable fuel

A: A
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Q: Over time, iron becomes rust when it combines with water and oxygen. Which type of change must occur for rust to form?
(A) chemical (B) mechanical (C) nuclear (D) physical

A:
A
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