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根据短文内容，选择正确答案。
There was once a man who couldn't sleep well because he was afraid that there was a stranger under his bed. He thought that as soon as he went to sleep, the stranger would come out from the bed and rob him. He was worried that the stranger might even kill him!
Every night, after he got into bed, the man had to get up again and looked under the bed. There was never anyone there, but as soon as he got back into bed, he had to get up and looked under the bed again. This went on for hours until at last he fell asleep from exhaustion.
The time came for the man to get married. He didn't tell his wife about his fears but she soon found out because he kept her awake all night.
“You must go to see a doctor,” she told him. “He will make you become well. You won't have such silly fear again.”
The man did as his wife told him. He told the doctor his problem, and the doctor said, “You can be well again, but it will take about two years. You must come and see me three times a week. The cost for each visit will be $75.”
The next day the man called the doctor and said, “I won't need to visit you again. I'm well now.”
The doctor was surprised. “How?” he asked. “Who made you get well?”
“My wife did,” the man said. “When I told her how much I would have to pay you, she cut the legs off the bed.”
