instruction:
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.
question:
Some scientists believe that the mass extinction of dinosaurs was caused by the impact of a large meteorite on Earth. This impact would have caused a darkening of the sky due to dust blown into the upper atmosphere. This darkening would have reduced the sizes of some ecosystems because of  
 (A) longer seasons. (B) accelerated erosion. (C) reduced photosynthesis. (D) increased number of hurricanes.
answer:
C


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


question:
One key physical process in beach formation is wave action. Sand is deposited on beaches as waves break onto the shoreline and the energy from the wave scatters. Which type of energy is most used by wave action to modify the shape of the beaches?  
 (A) thermal (B) potential (C) chemical (D) mechanical
answer:

D