单选题 Smoking is considered dangerous to the health. Our tobacco--seller, Mr. Johnson, therefore, always asks his customers, if they are very young, whom the cigarettes are bought (51) . One day, a little girl whom he had never seen before walked (52) into his shop and demanded twenty cigarettes. She had the (53) amount of money in her hand and seemed very sure of herself. Mr. Johnson was so (54) by her confident manner that he (55) to ask his usual question. (56) , he asked her what kind of cigarettes she wanted. The girl replied (57) and handed him the money. While he was giving her the change, Mr. Johnson said laughingly that (58) she was so young she should (59) the packet in her pocket in case a policeman saw it. (60) , the little girl did not seem to find this very funny. Without (61) smiling she took the (62) and walked towards the door. Suddenly she stopped, turned (63) , and looked steadily at Mr. Johnson. There was a moment of silence and the tobacco-seller (64) what was going to say. All at once, in a clear, (65) voice, the girl declared, " My dad is a policeman," and with that she walked quickly out of the shop.