Read the passage and choose the best answer to the following questions.
Visitors who want to see the city’s attractions have several transportation options. The use of private cars is discouraged, since parking is limited and the streets of the historical district are narrow. Fortunately, excellent alternatives are available. The subway system provides fast, inexpensive transportation to all areas of the city, from 6:00 am to 12 midnight. Bus service operates 24 hours a day, for those who prefer to travel above ground and sneak in some extra sightseeing on route. Those of you who want to make sure that you see all the tourist attractions may be especially interested in our Visitor’s Tour buses, which make stop at all points of interest throughout the city. For your convenience, special visitor’s passes for all forms of public transportation are sold at hotels throughout the city, along with maps and schedules for transportation routes. Subway tickets may be also be purchased at subway stops.
Which services stops at night?
A.Tour service
B.Subway service
C.Bus service
D.Taxi service