A、It has no windows. B、People get onto it at the front. C、It has two carriages. D、It is open at the back. D

M: Hello, everyone. (12-1) Today we have Linda Forbus from the Department of Transport, and she is here to talk about a typically British way to travel.
W: (12-2) Ah, yes. It’s on a bus—or, to be exact, on a red double-decker bus. Double-decker buses are buses that have two levels—an upstairs and a downstairs. You see them in other countries too, but for lots of people a red double-decker bus is a typical London sight.
M: Actually, if you think about a red London bus, (13) you’re probably thinking about one special kind of double-decker bus called the Routemaster. The one that’s open at the back.
W: That’s right. You get onto the bus at the back—there isn’t a door; it is open.
M: And you can just jump on or off the bus. (14) Bit dangerous.
W: Yeah, a bit. But, in fact, we don’t really have that typical red double-decker Routemaster bus any more.
M: Yeah, we do—I saw one this morning.
W: Well, we do still have them on one or two bus routes right in the centre of London but I think that’s sort of a tourist thing, really. Buses nowadays are mostly new double-deckers. They’re still red—or the very long single-decker buses—the ones we call bendy buses.
M: Oh, yeah, I don’t like those bendy buses.
W: (15) But they’re much easier to get on for people in wheelchairs, or mums with babies in pushchairs or old people who can’t walk very well. That was one of the main reasons that they stopped using the Routemaster buses.
M: Oh right, I didn’t know that.
W: So people like to see the old-fashioned Routemaster buses and tourists like to see them too, but it’s probably better to travel on the new buses—they’re definitely more comfortable.
Questions 12 to 15 are based on the conversation you have just heard.
12. What are the speakers talking about?
13. What is special about the Routemaster?  
14. What does the man think of the Routemaster?
15. Which was the main reason that bendy buses replaced the Routemaster?