单项选择题

(B)
Some years ago, an American policeman found a woman lying near a lonely road. She did not appear to have had an accident, but she was trembling, and clearly in a state of shock, so he rushed her to the nearest hospital. She began to tell the doctors on duty a story which was astonishing. She had been driving along a country road when she had been stopped by a flying saucer (飞碟) landing in front of her. She had been forced to leave the car and enter the flying saucer by creatures which looked like human beings and which could easily make themselves understood although they could not speak. It was as though they could read her thoughts and she theirs. They treated her politely and allowed her to leave after carrying out a number of tests on her. As she otherwise seemed to be normal, the doctor decided that she was probably suffering from the side effects of some drug. The woman insisted on being allowed to go home, but when she gave her address it was in a town over a thousand miles from the hospital. The police then started to look into the matter and soon discovered that there was already a search going on for the woman, whose husband had reported that she had disappeared. Her car had been found with the driver’s door open and the engine running. In front of the car the surface of the road had been completely destroyed not by an explosion or anything of that kind, but as though a large, circular, white-hot object had burnt through it. Which of the following about the flying saucer is NOT mentioned in this article