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. I don’t know who invented _____ telephone, it’s really _____ most useful invention.
A. the; a B. the; the C. a; a D. 不填；不填
22. Tom as well as his parents_______going to Japan next week.
A. are B. is C. will D. was
23. Mother gave me 2000 Yuan, most of _______ used for my school fees.
A. them were B. it was C. that was D. which was
