阅读下列短文，从每题所给的四个选项（A，B，C和D）中，选出最佳选项。

　　Astronomers do not always agree with each other. One thing on which they cannot agree is the origin of the universe. The universe includes millions of galaxies(星系). Each galaxy is made up of billions of stars. Our earth the moon and the sun are part of the same galaxy. We call this galaxy the Milky Way.

　　No one can tell us exactly how the universe came into being. Astronomers can only give us their theories on the way it began. Guesses based upon serious research and study are called theories.

　　One such theory is known as the“big bang”theory. It claims that all matter in the universe was made happening at the same time as a result of a giant explosion about 10 billion years ago.

Other astronomers do not accept the“big bang”theory. Their idea is called the“steady state”theory. These astronomers believe there was no sudden beginning to the universe just as there will be no sudden end. They say matter has always been created at a constant rate and will go on being created forever. Other people have still other theories but there is as yet no way of proving or disproving any of them.

　　Through the use of their instruments scientists have learned that the galaxies are moving away from each other. Scientists may not be able to agree with each other on how the universe began. But they do agree that the universe is growing. They also admit men have much to learn before they can solve the puzzle of the universe.

1．From the story we know ________.

[　　]

A．the universe should come to an end at once

B．the universe has too many galaxies in it

C．scientists need instruments in their work

D．scientists can only give us theories

2．On the whole the article tells about ________.

[　　]

A．a good way to prove scientific theories

B .theories about the origin of the universe

C．forcing scientists to agree with each other

D．how to prove a theory

3．Which statement does the article lead you to believe?

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A．The universe may puzzle men for a long time.

B．No one wants to know how the universe began.

C．The universe can never puzzle the astronomers.

D．Astronomers can not agree on anything.