Which One of the Following Statements Is Not a Consequence

Multiple Choice

Which one of the following statements is not a consequence of the second law of thermodynamics?

A) The efficiency of any engine is less than 100%.
B) The natural direction of heat flow is from hot to cold.
C) A motor can operate using the atmosphere as a heat reservoir.
D) Only reversible processes have a zero net entropy change for the universe.
E) There is zero net entropy change for the universe in the operation of a real refrigerator.