完形填空
阅读下面的短文，文中有15处空白，每处空白给出了4个选项，请根据短文的内容从4个选项中选择1个最佳答案。
Singing Alarms Could Save the Blind
If you cannot see, you may not be able to find your way out of a burning building —— and that could be fatal. A company in Leeds could change all that ___1__ directional sound alarms capable if guiding you to the exit. Sound Alert, a company ___2___ the University of Leeds, is installing the alarms in a residential home for ___3__ people in Sommerset and a resource centre for the blind in Cumbria. ___4___ produce a wide range of frequencies that enable the brain to determine where the ___5__ is coming from. Deborah Withington of Sound Alert says that the alarms use most of the frequencies that can be ___6___by humans."It's a burst of white noise __7___ 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 __8___ room. It __9___ them nearly four minutes to find the door __10____ a sound alarm, but only 15 seconds with one. Withington studies how the brain __11____sounds at the university. She says that the __12___ of a wide band of frequencies can be pinpointed more easily than the source of a narrow band. Alarms ___13____ 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 __14___ down stairs. They were __15__ with the aid of a large grant from British Nuclear Fuels.
1. A. without B. with C. having D. selling
2. A. run by B. changed by C. decorated by D. criticized by
3. A. slow B. deaf C. blind D. lame
4. A. Alarms B. Alarm C. The alarm D. The alarms
5. A. noise B. sound C. music D. bell
6. A. watched B. produced C. learnt D. heard
7. A. where B. what C. that D. how
8. A. smoked B. smoke-filled C. filled with smoke D. smoke-filling
9. A. has taken B. takes C. took D. will take
10. A. on B. near C. without D. from
11. A processes B. produces C. possesses D. proceeds
12. A. feature B. quality C. diagram D. source
13. A. basis on B. base on C. basing on D. based on
14. A. or B. and C. but D. otherwise
15. A. developed B. determined C. discovered D. delivered
