In the summer of 1980 a Spanish tourist, Gaspar Carner, went to Great Britain on holiday. When he was travelling in Scotland, he decided to visit Loch Ness, the famous lake where people say there is a monster. But while he was going across the lake in a boat, his bag fell into the water. In the bag were his passport, car keys, pen, and all his money. Loch Ness is 150 metres deep, so he didn't expect to see the bag again! Fourteen years later, in 1994, some scientists decided to explore the lake. They looked for the Loch Ness monster. Suddenly one of them saw something black in the water. They carefully went nearer. They thought the black thing was the monster. They went nearer and nearer. It was a bag. They took the bag out of the lake. They found that the photo on the passport was still clear. One of the scientists happened to be familiar with Gaspar Carner. So the bag was returned to him. The reason why the lake is famous is that   _  .
it's very deep there may be a monster there's a bag in it it's in Scotland
Question: In the summer of 1980 a Spanish tourist, Gaspar Carner, went to Great Britain on holiday. When he was travelling in Scotland, he decided to visit Loch Ness, the famous lake where people say there is a monster. But while he was going across the lake in a boat, his bag fell into the water. In the bag were his passport, car keys, pen, and all his money. Loch Ness is 150 metres deep, so he didn't expect to see the bag again! Fourteen years later, in 1994, some scientists decided to explore the lake. They looked for the Loch Ness monster. Suddenly one of them saw something black in the water. They carefully went nearer. They thought the black thing was the monster. They went nearer and nearer. It was a bag. They took the bag out of the lake. They found that the photo on the passport was still clear. One of the scientists happened to be familiar with Gaspar Carner. So the bag was returned to him. The reason why the lake is famous is that   _  .
A. it's very deep
B. there may be a monster
C. there's a bag in it
D. it's in Scotland
Answer: