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:
Which best describes a characteristic of the jet stream?  
 (A) It forms a boundary between a cold air mass and a warm air mass. (B) It creates the high winds around the eye of a hurricane. (C) It forces the hot air along the equator to rise to areas in North America. (D) It causes high pressure air masses to rotate clockwise.

Ex Output:
A


Ex Input:
The transfer of heat in the atmosphere by winds that circulate between the equator and the poles is an example of  
 (A) radiation. (B) insulation. (C) convection. (D) conduction.

Ex Output:
C


Ex Input:
Which statement is an opinion?  
 (A) Chemistry and Physics are major branches of science. (B) Life Science is a subject filled with interesting information. (C) Geology and Oceanography are subjects in Earth Science. (D) Biology is a science that studies complex organisms.

Ex Output:

B