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:
Solar radiation provides more heat near the equator than near the poles on Earth. The greatest amount of heat is moved away from the equator by  
 (A) ocean currents. (B) aquatic plants. (C) surface winds. (D) tectonic plates.

Ex Output:
A


Ex Input:
Which unit is used to express the amount of energy in food?  
 (A) Calorie (B) degree Celsius (C) milliliter (D) gram

Ex Output:
A


Ex Input:
Which movement of carbon between reservoirs takes the longest to achieve?  
 (A) from burning coal to the atmosphere (B) from plant tissues to coal in the crust (C) from the atmosphere to the sugars in plants (D) from the respiration of fish to the ocean waters

Ex Output:

B