The correct definition of "point of imitation" is:

a. the term for a musical cliché in which the music tries to sound out themeaning of the text

b. a distinctive motive that is sung or played in turn by each voice orinstrumental line.
c. when one composer emulates another by borrowing entire polyphonicsections of an earlier work.
d. imitation of a complete subject at a fixed interval and time delay.

b