In this task, you need to answer basic science questions. For each question, several terms are intentionally masked with ***. This masking can cover very few or many of the question words. Clearly, if masked terms are important, the modified question will be impossible to answer. Please indicate the correct answer with one of the following responses: "A", "B", "C", "D" or "E". While "A"-"D" correspond to the answer options provided in the input, "E" represents "I don't know" for questions that do not provide enough information. Respond via "E" if the question is not answerable. Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D', 'E'.

Ex Input:
Question: Tyrone put two *** in a plastic bottle of water and shook it. After he stopped shaking the bottle, he observed that small pieces of the *** were floating in the water. What is the best *** he can make based on this observation? If shaking the bottle causes pieces of *** to *** off, ___.  (A) then using cold water will break off more pieces (B) then using hot water will make the stones change colors (C) then shaking for a longer amount of time will break off more pieces (D) then shaking for a shorter amount of time will make the rocks change color.

Ex Output:
C.


Ex Input:
Question: John was *** his *** *** when it *** *** ***. What is the *** *** *** should do to *** *** the ***?  (A) recharge the battery (B) take the player apart (C) replace the player with a new one (D) change to a different son.

Ex Output:
E.


Ex Input:
Question: A rock on top of a mountain is measured at 30 feet high in 1957. Fifty years later, in 2007, the rock is measured again and is now 21 feet high. What term best describes the reason for the rock's change in height?  (A) weathering (B) wind erosion (C) water erosion (D) chemical erosio.

Ex Output:

A.