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.

[EX Q]: Sickle cell anemia is a genetic disease caused by an autosomal recessive gene. If each parent carries one sickle cell allele, what are the chances that their child will have sickle cell anemia?  
 (A) no chance (B) one in four (C) two in four (D) three in four
[EX A]: B

[EX Q]: What causes ocean water to evaporate in the water cycle?  
 (A) energy from the Sun (B) energy from ocean waves (C) energy from Earth's rotation (D) energy from Earth's moon
[EX A]: A

[EX Q]: Which of the following would most likely happen if grasses and shrubs were removed from a rural Massachusetts ecosystem?  
 (A) There would be an increase in consumers in the ecosystem. (B) There would be an increase of photosynthesis in the ecosystem. (C) There would be a decrease in food energy produced by the ecosystem. (D) There would be a decrease of carbon dioxide available to the ecosystem.
[EX A]:
C