[单选题]通信员应当履行的战备职责是?
A.掌握辖区交通道路、消防水源、消防安全重点单位等情况和灾害事故处置程序及行动要求,熟悉执勤战斗预案的有关内容;掌握本班人员情况,确定战斗分工;熟悉执勤战斗装备配备和使用操作技术,认真组织维护、保养工作,使其随时处于良好战备状态;妥善处理本班战备工作中发生的问题,并及时报告中队值班首长。副班长协助班长工作。在班长离开岗位时,代行班长职责。
B.了解辖区交通道路、消防水源、消防安全重点单位等基本情况;保持个人防护装备和分管装备完整好用,熟悉装备性能,熟练操作使用;掌握辖区主要灾害事故处置的行动要求,熟悉中队执勤战斗预案中本岗位的主要任务;熟悉灭火救援行动安全要则,掌握紧急避险方法。
C.掌握火警和应急救援分级规定,坚守岗位,按照出动命令或者报警及时发出出动信号,并做好记录;熟练使用通信系统和装备,做好维护保养工作,发现故障及时处理;掌握辖区交通道路和消防安全重点单位等有关情况,熟记通信用语和有关单位、部门的联系方法;
D.熟悉辖区市政和消防安全重点单位内部消火栓的数量、位置、给水管网形状、直径、供水能力;熟悉辖区内天然水源以及其他可用水源的情况和取水方式; 掌握供水装备技术性能和供水方法;保持分管装备完整好用,熟练使用相关装备;负责消防水源资料登记、造册、归档工作,定期对消防水源进行检查。

There are some steps you can take yourself to avoid catching a cold. Contrary to popular belief, colds are not caused by exposure to severe weather. Colds are caused by viruses (病毒) harbored in the body, and you’ re better off out on the ski slopes or even waiting for the bus on a snowy day than you are in a warm room, surrounded by friends, co-workers, or fellow students, who just may be passing the viruses around. If you feel a chill when you’ re coming down with a cold, you’ re already sick. A chill is an early symptom: it’ s the cold that caused the chill, not the other way around.
While the virus can spread through droplets(飞沫) propelled into the air when a cold-sufferer coughs or sneezes. Surprisingly, this is not the most common mute of transmission. Numerous studies have now shown that the overwhelming majority of colds are "caught" by hand contact. A cold sufferer rubs her nose, thereby transferring the virus to her hand.
A. Colds and Viruses
B. Ways to Avoid Colds
C. The Spread of Viruses
D. Hand Contact and Transmission of Viruses