题目内容：

Three men traveling on a train began a conversation about the world's greatest wonders.

“In my opinion，”the first man said，“the Egyptian pyramids are the world's greatest wonder.Although they were built thousands of years ago，they are still standing.And remember：the people who built them had only simple tools.They did not have the kind of machinery that builders and engineers have today.”

“I agree that the pyramids in Egypt are wonderful，”the second man said，“but I do not think they are the greatest wonder.I believe computers are more wonderful than the pyramids.They have taken people to the moon and brought them back safely.In seconds，they carry out mathematical calculations that would take a person a hundred years to do.”

He turned to the third man and asked，“What do you think is the greatest wonder in the world？”

The third man thought for a long time，and then he said，“Well，I agree that the pyramids are wonderful，and I agree that computers are wonderful，too.However，in my opinion，the most wonderful thing in the world is this thermos.”

And he took a thermos out of his bag and held it up.

The other two men were very surprised.“A thermos？”they exclaimed.“But that's a simple thing.”

“Oh，no，it's not，”the third man said.“In the winter you put in a hot drink and it stays hot.In the summer you put in a cold drink and it stays cold.How does the thermos know whether it's winter or summer？”

1.The three men could not agree on what the world's greatest wonder was because        ．

 

A. they could not think of anything very wonderful

B. they all had different ideas

C. they could not prove that their opinions were right

D. the journey ended too soon

2.The first man thought the pyramids were the most wonderful things in the world because        ．

A. they were very beautiful

B. they were Egyptian

C. they had been built with very simple tools

D. they could do mathematical calculations

3.The third man thought a thermos was the most wonderful thing in the world because        ．

A. it lasted longer than the pyramids

B. it cost less than a computer

C. he thought it knew whether it was winter or summer

D. the other two men were surprised when he told them about it