You are given a science question (easy-level) and four answer options (associated with "A", "B", "C", "D"). Your task is to find the correct answer based on scientific facts, knowledge, and reasoning. Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D'. There is only one correct answer for each question.

When coal is burned to produce electricity, the electrical energy produced is less than the potential energy in the coal. Which best explains this observation?
(A) As coal is heated, some of the molecules move so fast that they are destroyed. (B) Some of the energy in coal is destroyed by the intense heat required to release its potential energy. (C) Some of the potential energy in coal is converted into forms of energy other than electricity. (D) The amount of potential energy in fuels is overestimated.
C