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'.

Example Input: Question: *** *** source *** *** all heat energy *** Earth ***?  (A) Wind (B) Water (C) The Sun (D) The Moo.
Example Output: C.

Example Input: Question: A *** can *** a serious disease. When a *** *** is developed, it is given to a *** *** of people. Why would it be *** to *** each *** on a *** *** of *** *** every*** can have one?  (A) to figure out how much the vaccine is worth (B) to determine how the vaccine will affect people (C) to understand how that disease affects the human body (D) to find out how many people are affected by the diseas.
Example Output: B.

Example Input: Question: How would the *** *** in a forest area most likely be *** if a *** development is built in that area?  (A) They would produce more offspring. (B) They would change the color of their feathers. (C) They would experience a decrease in available food. (D) They would experience a decrease in competition.
Example Output:
C.