A、They often ride a motorcycle. B、They used to ride a horse. C、They work in the mountains of Canada. D、They ride a horse. B文中说骑誓

Everyone knows about the Royal Canadian Mounted Police, but (29) nowadays the romantic red uniform jacket is only worn on special occasions, and the famous horses are rarely seen. So the "Mountie", as a member of this police force is known, is not, in fact, often mounted except on a powerful motor-cycle. (30)He is a member of a very modern and efficient organization.
     The Royal Canadian Mounted Police has responsibility for an enormous area, from the U.S. border up to the vast ice-fields and frozen lakes. (30)A mountie may work in the Headquarters building in Ottawa. He may pilot a patrol plane across the snow-deserts in the north. He may be doing customs work at the frontier. He may be in plain clothes watching for s suspicious character at an airport, or he may simply be driving a patrol-car.
     There are more than ten thousand men in this force, and it was one of these who was responsible for the arrest of James Earl Ray. Police all over the world were looking for Ray after the murder of Martin Luther King. In June 1968, a group of policemen in Canada were doing routine work with applications for passports. Suddenly one man noticed a photo which looked very much like Ray. The name was different, but the resemblance was so strong that (31) the police started to investigate. They discovered that the man had already gone to Britain. The photograph and the finger-prints were sent to the British police, who arrested Ray at London Airport, when he was just going to get on a plane for Brussels. The murder that had shocked the world was solved by a mountie on Ottawa.