第6部分：完形填空(第51～65题，每题1分，共15分)
下面的短文有15处空白，请根据短文内容为每处空白确定1个最佳选项。
Singing Alarms Could Save the Blind
If you cannot see, you may not be able to find your way ______ (51) of a burning building—and that could be fatal. A company in Leeds could change all that with directional sound alarms capable of guiding you to the exit.
Sound Alert, a company ______ (52) the University of Leeds, is _______ (53) the alarms in a residential home for blind people in Sommerset and a resource centre for the blind in Cambria. _______ (54) produce a wide range of frequencies that enable the brain to determine where the ______ (55) is coming from.
Deborah Withington of Sound Alert says that the alarms use most of the frequencies that can be ______ (56) by humans. “It is a ______ (57) of white noise that people say sounds like static on the radio,” she says. “Its life-saving potential is great.”
She conducted an experiment in which people were filmed by thermal-imaging cameras trying to find their way out of a large ______ (58) room. It ______ (59) them nearly four minutes to find the door ______ (60) a sound alarm, but only 15 seconds with one.
Withington studies how the brain ______ (61) sounds at the university. She says that the source of a wide ______ (62) of frequencies can be pinpointed more easily than the source of a narrow band. Alarms _____ (63) the same concept have already been installed on emergency vehicles.
The alarms will also include rising or falling frequencies to indicate whether people should go up ____ (64) down stairs. They were ____ (65) with the aid of a large grant from British Nuclear Fuels.
51. A in B out C behind D under
52. A run by B changed by C decorated by D criticized by
53. A installed B installs C installing D had installed
54. A Alarms B Alarm C The alarm D The alarms
55. A noise B sound C music D bell
56. A watched B produced C learnt D heard
57. A amount B lot C burst D deal
58. A smoked B smoke-filled C filled with smoke D smoke-filling
59. A has taken B takes C took D will take
60. A on B near C without D from
61. A processes B produces C possesses D proceeds
62. A range B lot C variety D band
63. A basis on B base on C basing on D based on
64. A or B and C but D otherwise
65. A developed B determined C discovered D delivered