单项选择题

From the beginning rivers have played an important part in the life of man. Man of the earliest times used the rivers as a means of travel. Today rivers still serve as a great waterway for the transport and people.
In ancient times, man settled near rivers or on river

Rivers have been important to man ()

A.since the last century
B.for a very long time
C.since a few hundred years ago
D.since a few years ago