Here are the correct answers:

19. Seventy dollars **A. is** too much to pay for that shirt.
20. A number of students **B. are** going to the class picnic.
21. Either John or his wife **B. makes** breakfast each morning.
22. The majority of students **B. believes** him to be innocent.
23. The crowd at the basketball game, **C. was** will with excitement.
24. The young **A. have** the future in their hand.
25. The picture of the soldiers, **B. brings** back many memories.
26. Three weeks **C. was** not enough for holiday.
27. Each of you **C. has** a share in the work.
28. A number of students **B. has** volunteered to the job.
29. Linguistics **D. finds** out the ways in which languages work.
30. The Philippines, **D. consists** of more than 7,000 islands.
31. The United Nations **C. has** its headquarters in New York city.
32. One of my neighbours **C. is** curious about other people's private life.
33. Tom doesn't agree but the rest of us **C. do**.
34. There **B. were** a few flowers in this garden last summer.
35. A large number of reporters, **C. are** at the meeting yesterday.