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: *** *** are *** from *** *** in a *** center. Which of the following is the *** *** the *** *** can *** the *** *** from the *** cans?  (A) sort the cans by size (B) put the cans in water (C) cool the cans to a low temperature (D) put the cans under an electromagne.

Ex Output:
E.


Ex Input:
Question: Which is the best example of ***?  (A) using low energy appliances (B) washing and reusing plastic cups (C) using empty milk cartons as flower planters (D) using aluminum cans to make new product.

Ex Output:
E.


Ex Input:
Question: *** *** an *** to *** if the *** of *** *** in the *** *** to his ***. How should he *** his investigation?  (A) Count the number of earthworms that are already there (B) Make sure that there are no other organisms located in the soil (C) Clean out the plants in the garden (D) Make sure that the soil is mois.

Ex Output:

E.