One of the Reasons for the Recent, Rapid Growth of Direct

One of the reasons for the recent, rapid growth of direct marketing in American society is the:

A) fact that the U.S.has moved from an industrialized nation to a service nation.
B) increase in the number of hours individuals spend on watching television.
C) non-proliferation of cellular phones.
D) increased use of consumer credit cards.
E) development of four-color printing presses.