4. Which one of the following statements of the first law of thermodynamics is correct?
(A) In a reversible process the entropy of an isolated system increases; in an irreversible process the entropy stays constant.
(B) It is impossible for a heat engine that operates in a cycle to convert its heat input completely into work
(C) As the temperature of a system approaches absolute zero, all processes stop and the entropy of the system approaches a minimum value.
(D) It is impossible for a cyclical device to transfer heat continuously from a cold body to a hot body without the input of work or other effect on the environment.
(E) The change in the internal energy of a system is equal to the sum of the energy transferred across the system boundary by heat and the energy transferred by work.