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:
Many sports stadiums use grass, but some use fake grass called artificial turf. Artificial turf is made of fibers that look like real grass. In which way is this technology most likely beneficial?  
 (A) It uses less water. (B) It produces more heat. (C) It releases less moisture. (D) It absorbs more carbon dioxide.

Ex Output:
A


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:
Centuries ago, people used their knowledge of the stars to  
 (A) navigate ships. (B) study the weather. (C) predict volcanic eruptions. (D) map the Earth's surface.

Ex Output:

A