英语阅读理解,根据短文内容回答问题

英语阅读理解,根据短文内容回答问题
Miss Mona lived alone in a small flat.She was old and did not like noise at all,so she was very pleased when the noisy young man and woman who lived in the flat above her moved out.A new young man moved in and Miss Mona thought,“Well,he looks silent.”
But at three o’clock the next morning,Miss Mona was woken up by the barking of a dog.She thought,“I have never heard a dog here before.It must belong to the new man in the flat above.” So she telephoned the young man,said some unpleasant words to him about the dog and then hung the telephone up before he could answer.
Nothing more happened the next morning.Then Miss Mona’s telephone rang.When she answered,a voice said,“I am the man above.I have rung up to say that I haven’t a dog.”
Whom did the dog belong to?