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 Input:
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.

Ex Output:
C


Ex Input:
Your community is planning to build a new sanitary landfill. In locating the landfill, which is the most important environmental consideration?  
 (A) the cost of the land (B) the location of the groundwater (C) the proximity to an industrial park (D) the accessibility to a major highway

Ex Output:
B


Ex Input:
Shale is a common sedimentary rock. Which of these was required to form shale?  
 (A) evaporating (B) condensing (C) melting (D) compacting

Ex Output:

D