Choose a sentence A, B, C or D that has the same meaning as the given sentence

Choose a sentence A, B, C or D that has the same meaning as the given sentence
37: Nowadays /a lot of / important inventions / be / carried out / by scientists .
A. Nowadays, a lot of important inventions are carried out by scientists .
B. Nowadays a lot of important inventions be carried out by scientists .
C. Nowadays a lot of important inventions is carried out by scientists .
D. Nowadays a lot of important inventions was carried out by scientists .
38: Tom said: “I want to buy a science book .”
A. Tom said I wanted to buy a science book .
B. Tom said he want to buy a science book .
C. Tom said he wanted to buy a science book .
D. Tom said he wants to buy a science book .
39: She said: “I was waiting for the bus when he arrived”.”
A. She said that he has been waiting for the bus when he arrived.
B. She said that he had waiting for the bus when he arrived .
C. She said that she had been waiting for the bus when he had arrived .
D. She said that she had been waiting for the bus when him arrived.
40. Do more exercise, and you can keep fit.
A. If you did more exercise, you could keep fit.
B. In case you do more exercise, you couldn’t keep fit.
C. If you do more exercise, you can keep fit.
D. Unless you do more exercise, you could keep fit.