)The London Underground (usually called the tube) is the biggest subway system in the world. It is also the fastest way to travel in the city. The network consists of nine major routes called “lines”.
You can buy tickets at any underground station at a ticket office, or from a ticket machine. Some of the ticket machines require exact money. All of the machines display “Change given” or “Exact money only” signs. The price of the ticket depends on the length of the trip. The longer the trip, the higher the cost of ticket.
Train stop at all stations. On some trains, passengers need to press a button to open doors. Every underground train car has maps that show all the stations on the line you are traveling on. There is a map of the whole underground system in every station.
Smoking is not allowed on underground trains or in stations.

(1). (单选题) According to the passage, the other name of the subway in London is ___.( )(本题2.5分)

A、 the subway system
B、 the underground
C、 the tube
D、 the lines

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