The correct answer is D) When heat is transferred from one body to another, the internal energy given up by the first body must be equal to the internal energy taken up by the second body. This statement represents the first law of thermodynamics, which states that energy can be converted from one form to another, but it cannot be created or destroyed. When heat is transferred from one body to another, the internal energy given up by the first body must be equal to the internal energy taken up by the second body, as energy is conserved in this process. The other options are incorrect because they do not accurately represent the first law of thermodynamics. Option A) suggests that the internal energy given up by the first body must be greater than the internal energy taken up by the second body, which is not the case. Options B) and C) do not correctly describe the relationship between the internal energies of the two bodies.