题目

 “Everything happens for the best”, my mother said whenever I faced disappointment. “If you  21  on, something good will happen some day.”    Mother was right, as I  22  after graduating from college. I had designed myself for a  23  announcer. So I went to Chicago to knock on the door of every station and was  24  every time. In one station, a kind lady told me that   25  stations wouldn’t employ a person without   26  since I had just graduated. “Go out in the town and find a small station that might give you a chance,” she said.    I returned to Dixo在同一个平面上，若一条直线把一个平面分成个部分，两条直线把一个平面最多分成个部分，三条直线把一个平面最多分成个部分，则20条直线把一个平面最多分成的部分个数为 [     ]A.201B.206C.209 D.211