完形填空（每小题1分，满分20分） 请认真阅读下面短文，从短文后各题所给的A、B、C、D四个选项中，选出最佳选项，并在答题卡上将该项涂黑。 In the north of Scotland there is a lake called Loch Ness. It is the biggest in Britain. It is over thirty kilometersand in some places nearly 300 meters deep . It is cold and dark and not many people went there until after 1930. Then a road was made the lake. Holiday makers began to use the road, and this was when the began. Someone said that he had seen a monster（怪兽）in the lake. He said it was twelve meters long. It had a long and a small head. Then someone else said he had seen. Others said the same thing and in 1933 a London doctor took a. It like a monster with a long neck and a thick body but the photo was not too. The newspapers printed the picture and it the Loch Ness monster, or "Nessie". Then the argument began. people, however, were certain there was something living in the lake. Others said there was there. In 1961, a lot of people joined together to make a real to see and photograph the monster to find there was one! Several times people thought they saw something but after ten years there was no hard evidence. Later underwater television cameras were used, but found any real proof（证据）. However, they find something interesting: a huge underwater cave. It was big enough to be of a monster, but of course, this was not a proof. In 1975, however, some American scientists a search group. They used an underwater camera. It took pictures every seventy seconds. Some of the pictures seemed to show a red-brown creature. Its body was about four meters long had a very ugly head on the end of a four -meter neck. Many people then began to believe in the monster. But even today we can't be certain.