1. (2019·扬州模拟) 阅读理解

    The monarch is one of the most beautiful butterflies. It is famous for its yearly migration（迁徙）from the northern part of North America to Mexico, There, millions of monarchs spend the winter together in one small area. This migration is one of the greatest wonders of nature. Yet this behavior has now put the monarch at risk.

    Every September, millions of monarchs from the United States fly to Mexico. After about two months of flying time, they reach their sanctuary(庇护所)in central Mexico. Then, in the warm climate of private and quiet valleys, far from most human activity, the butterflies create one of nature's great scenes. They cover every tree with bright color. The show lasts until spring, when the butterflies return north.

    While they are all crowded together, the monarchs are highly weak. If the environment in those valleys was disturbed, the whole species could be hurt or even die out. That is why for many years scientists who knew about the monarchs' winter sanctuary kept the location a secret.

    In recent years, however, the monarchs' secret has been discovered. Today, the butterflies' winter sanctuary is crowded with tourists, who disturb the environment. Worse still, local farmers who need more land to farm have begun to take up the area. They are cutting down trees, making it difficult for the butterflies to survive. They should not farm in the monarchs' sanctuary.

    People should act immediately to protect the species' winter sanctuary. Local farmers must be helped so that they no longer need to take land from the butterflies. Tourist visits to the butterflies' hidden valleys must also be limited. Unless these steps are taken soon, in a few years the monarch butterfly of North America may be just a beautiful memory.

1. （1） What do we know about monarch butterflies?

   A . They fly to the US in autumn. B . They spend the winter together. C . They are the most beautiful butterflies.  D . They have been known to human beings until recent years.
3. （2） What is Paragraph 2 mainly about?

   A . The monarchs' diet. B . The monarchs' colors. C . The monarchs' life cycle. D . The monarchs' migration.
5. （3） Why did scientists keep the monarchs' winter sanctuary a secret?

   A . To keep the valleys from being destroyed. B . To stop farmers from cutting down trees. C . To do their research secretly D . To protect the monarchs.
7. （4） What is the purpose of the text?

   A . To tell about a great place to watch monarch butterflies. B . To provide information about monarch butterflies. C . To ask people to protect monarch butterflies. D . To call on people to save the environment.