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: One hot summer, a grassland experienced a drought. Which most likely happened in the ecosystem during this time?  
 (A) The competition for food among primary consumers increased. (B) Nutrients cycled through the system at a faster rate. (C) Less solar radiation was able to enter the system. (D) Secondary consumers became extinct.

A: A
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Q: Which is a trait that a child can inherit from its parents?  
 (A) eye color (B) a broken leg (C) length of hair (D) language skills

A: A
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Q: Just under half the oil that enters ocean water comes from natural oil seeps on the ocean floor. Just over half the oil in the oceans comes from human activities. Which human activity contributes the most oil to the oceans?  
 (A) transporting oil over the ocean surface (B) drilling for oil on the ocean floor (C) polluting land with oil that reaches the oceans in runoff (D) polluting air with oil that reaches the ocean in precipitation

A:
A
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