阅读下面短文，从短文后所给各题的四个选项(A、B、C和D)中，选出可以填入空白处的最佳选项。
"Everything happens for the best." my mother said whenever I felt disappointed. " 36 , and one day something good will happen. Then you'll realize it wouldn't have happened 37 the disappointment you had experienced 38 ." Mother was right, 39 I discovered after graduating from college, I had decided to try for a job 40 radio, then 41 my way up to a sports announcer. I hitchhiked (搭免费车) to Chicago and tried every station, but got 42 . In one studio, a kind lady told me big stations couldn't risk hiring inexperienced persons. "Try your luck in the 43 " she said.
