In this subtask, you will answer a simple science question. Please indicate the correct answer. If you're not sure about the answer, choose the last option "I don't know". Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D', 'E'. The "A"-"D" responses correspond to the answer options mentioned in the input. There is a 5th option "E" which should be used for questions for which you're not sure about the answer (e.g., when the questions do not provide enough information to answer).

Input: Consider Input: Question: To safely conduct an experiment using chemicals, what should students always do?  (A) Work in large groups. (B) Wear safety goggles. (C) Wear short sleeves. (D) Keep a window open?

Output: B.


Input: Consider Input: Question: In 24 hours, the Earth completes ___.  (A) one rotation on its axis (B) one rotation around the Sun (C) one orbit around Mars (D) one revolution around the Moo?

Output: A.


Input: Consider Input: Question: The reading on a barometer rises when the air  (A) pressure increases. (B) pressure decreases. (C) speed increases. (D) speed decreases?


Output: A.