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: The fusion reaction that fuels the Sun converts hydrogen into  
 (A) carbon. (B) iron. (C) neon. (D) helium.

A: D
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Q: A delta can be seen from the air at the mouth of the Mississippi River. This delta was formed by  
 (A) erosion. (B) weathering. (C) conservation of soil. (D) deposition of sediment.

A: D
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Q: Which statement best describes the Law of Superposition?  
 (A) Each sedimentary layer of rock represents 1,000 years of Earth's age, much like the rings of a tree. (B) In undisturbed layers of sedimentary rock, the upper rock layers are older than the lower rock layers. (C) In undisturbed layers of sedimentary rock, the lowest layers contain the older rocks. (D) Rocks that form near volcanoes are older than surrounding rock.

A:
C
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