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: *** *** *** *** *** *** *** *** *** ***  (A) the size of the guitar. (B) the metal on the guitar. (C) the wood on the guitar. (D) the vibrations of the string.

Ex Output:
E.


Ex Input:
Question: *** *** *** *** activities *** *** forest *** *** positive effect *** *** ecosystem?  (A) Clearing the land to build new homes (B) Planting new trees where old ones were cut down (C) Building a new highway through the area (D) Cutting down trees to make farmlan.

Ex Output:
B.


Ex Input:
Question: Bears growing fur in winter is an example of  (A) growth (B) adaptation (C) migration (D) variatio.

Ex Output:

B.