TASK DEFINITION: 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'.
PROBLEM: Question: Which of the following represents a *** ***?  (A) a sugar cube dissolving in water. (B) ice cubes forming in a freezer. (C) ice cream melting in a bowl. (D) a cake baking in an oven.

SOLUTION: E.

PROBLEM: Question: A student *** to *** a *** *** *** that will *** the same amount of *** *** *** it is ***. Which should the student do *** when *** the *** tube?  (A) make a data table of amounts of toothpaste (B) gather building materials (C) create models of old toothpaste tubes (D) draw a few possible solution.

SOLUTION: E.

PROBLEM: Question: *** *** resources on *** are either *** or nonrenewable. Whether a *** is *** or *** *** on how *** or *** the *** is ***. If the *** is used *** than it is ***, then the *** will, in time, disappear. Which *** *** the *** of a *** *** resource?  (A) A group of people swims in a river. (B) A construction crew builds an iron bridge. (C) A farmer grows vegetables to sell at a local market. (D) A person bakes a cake with electricity produced by a hydroelectric power plant.

SOLUTION:
E.