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 main function of a fish's fins is to help the fish  
 (A) reproduce (B) see (C) breathe (D) move

A: D
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Q: A student hypothesizes that algae are producers. Which question will best help the student determine if this is correct?  
 (A) Do algae consume other organisms? (B) Which organisms consume algae? (C) Do algae use sunlight to make food? (D) Could an ecosystem survive without algae?

A: C
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Q: There are some towns located in the valley of the Alpine mountains. During part of the year, these towns stay dark all day because the mountains block the Sun. During which season would the Sun be low enough in the sky that the village stays in the shadows?  
 (A) fall (B) spring (C) summer (D) winter

A:
D
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