B The mystery had reached its climax (高潮) The man had undoubtedly been murdered. However, no one present knew who could have killed such a kind person. It was therefore time to call in the great detective, who gave one searching glance at the corpse (尸体), and then used a microscope. 'Aha!' he jumped as he picked a hair off the dead man's coat 'The mystery is a mystery no longer. We have only to find the man who lost this hair, and the criminal will be in our hands. ' The chain of logic was complete, and the detective started to do his search. For four days and four nights he moved unobserved through the streets of New York, scanning closely every face, looking for a man who had lost a hair. On the fifth day he discovered a man pretending to be a tourist and his head was enveloped in a cap reaching below his ears. The man was about to board the Gloritania, and the detective lost no time in following him on board. 'Arrest him!' shouted the detective, and then, drawing himself to his full height, he took out the hair. 'This is his,' said the great detective, 'and it proves his guilt. ' 'Remove his hat,' ordered the ship's captain firmly. It was discovered that the man had no hair. 'Aha!' said the great detective without a moment's hesitation. 'He has committed not one murder, but about one million!' 60. Before the great detective arrived, it seemed that______. A. the man had died of natural causes   B. no one could possibly have murdered the man C. the mystery would be easy to solve  D. the dead man was covered with hair 61. The detective declared the mystery would be solved soon______. A. after he found the murderer      B. before he used the microscope C. after he found a hair           D. before he looked at the corpse 62. The tone of this story is______. A. scientific       B. serious         C. educational      D. humorous 63. The main idea of this story is that______. A. those using logic are not always logical   B. mysteries can be solved by observation C. detectives can never be trusted          D. guilt can be proved scientifically