根据短文内容,从各题所给的四个选项中选择一个最佳答案.
A college student stayed up all night
studying for his zoology(动物学) test the next day. The
following morning, 1 he entered the classroom, he saw ten birds on
the desks. Each bird was 2 with a sack(麻布袋) and
only the legs were outside.
The teacher told the students that the test
would be to watch each pair of bird legs and write down the name and the living
habits of each bird.
The student looked at each pair of bird
legs. 3 of them looked the same to him. He began to
get upset. He stayed up all night studying, but now he had to name birds by
their legs. The more he 4 about it, the sadder he got.
He 5 not think of any answers after a long time. He
went to the teacher's desk and said, "What a strange test! 6 could anyone tell differences among birds by
their legs? I'm afraid I have to take the exam later. "7 these words, the student put his test paper on
the desk and walked to the door.
The teacher was 8.The class was so big that he didn't know
every student's 9,
so when the student reached the door, the teacher 10 out, "One moment, boy, what's your name?"
The student pulled up his trouser legs and
said, "My dear teacher, can you guess my name by my legs?"