完形填空。从A、B、C、D四个选项中选出最佳答案。

    Mr. Smith lived in a village（村庄）. He had a few farms（农场） and about twenty people working for him. He often told them 1hard and be honest(诚实的).

    One day he went to a farm and worked with the workers there. Soon it was time 2 lunch. He put 3 nice bread on the table and went out. A few minutes later, he came back again but he couldn't find the bread. "Who ate 4 on the table?" he shouted.

    Some of the workers answered, "We didn't."  The others said, "We saw nothing."

    "Well," said Mr. Smith, "5 are a lot of mice(老鼠) in the rooms, you know. So I put some poison（毒药） in the bread. 6 they eat, they must die. Then I can kill them."

    As soon as he finished, four workers began to cry. "Oh, dear!"

    "7?" asked Mr. Smith.  "We ate the bread when you were out. We are going to die." One of them cried.  "8," Mr. Smith said 9 a smile, "I only 10 you. Use your head."

If steel is heavier than water, why are ships able to         on the sea?

炼铁的反应：CO+FeO=CO₂+Fe中，CO充当（　　）

有的同学认为“罪犯都是法院、检察院去判，做事都是有权的说了算，所以权利都在当官的手里，并不在我们人民手里”；也有的同学认为“我们还小，国家事务与我们无关”。请你结合所学知识对以上观点进行评析。