Which of the following statements is false?

a. There is a relationship between time and relevance.
b. An opportunity cost represents the benefits foregone because one course of action is chosen over another.
c. Incremental revenue and differential revenue are not the same thing.
d. If machine A has an annual operating cost of $30,000 and machine B has an annual operating cost of 26,000 the incremental cost of the 2 machines is $4,000.

c