从A, B,C,D四个选项中，选出可以填入空白处的最佳选项，并在答题卡上将该项涂黑。
21. —Excuse me, can you spare me a few minutes?
—_________?
A. What’s on B. What’s up C. What is it D. What’s more
22. Jenny nearly missed the flight doing too much shopping.
A. as a result of B. on top of C. in front of D. in need of
23. Knowledge is there for___ will seek it.
A. who B whoever C.whom D. whomever
