Venice is the "Queen" of the Adriatic Sea  . Every year thousands of people from all over the world travel to Italy to visit the city. Do you know why they like to go there for a visit? Venice is a very beautiful city. It is quite different from other cities in the world. There aren't any roads and streets in the city. So there aren't any cars and buses. There are many canals in the city. There is one big canal and one hundred and seventy-seven small canals. People move up and down the canals in boats to go to work, go shopping or visit their friends. But Venice is sinking. It is going down and the water is going up. In 2040Venice will be under water, The Adriatic Sea will cover the city. The Venetians  love their city and want to stay there. So they want to save Venice? They can build some strong huge walls and gates in the sea. The gates will close to keep too much water out. Thus Venice will not sink. People from all parts of the world go to visit Venice because  _  .
there are 177 canals in the city. it is sinking into the Adriatic Sea. there are a lot of kinds of boats on the canals. it is not only beautiful but also quite different from other cities.
Question: Venice is the "Queen" of the Adriatic Sea  . Every year thousands of people from all over the world travel to Italy to visit the city. Do you know why they like to go there for a visit? Venice is a very beautiful city. It is quite different from other cities in the world. There aren't any roads and streets in the city. So there aren't any cars and buses. There are many canals in the city. There is one big canal and one hundred and seventy-seven small canals. People move up and down the canals in boats to go to work, go shopping or visit their friends. But Venice is sinking. It is going down and the water is going up. In 2040Venice will be under water, The Adriatic Sea will cover the city. The Venetians  love their city and want to stay there. So they want to save Venice? They can build some strong huge walls and gates in the sea. The gates will close to keep too much water out. Thus Venice will not sink. People from all parts of the world go to visit Venice because  _  .
A. there are 177 canals in the city.
B. it is sinking into the Adriatic Sea.
C. there are a lot of kinds of boats on the canals.
D. it is not only beautiful but also quite different from other cities.
Answer: