What is the most important reason for limiting the number of main points in a speech?（）

A.It is hard to maintain parallel wording if there are too many main points.

B.It is hard to phrase the central idea if a speech has too many main points.

C.It is hard to organize supporting materials if there are too many main points.

D.It is hard for the audience to keep track of too many main points.

正确答案：It is hard for the audience to keep track of too many main points.