97免费在线观看视频,亚洲综合自拍网,黄色毛片免费观看,热久久综合网,免费看日产一区二区三区 狠狠操av,久久久涩涩涩,在线精品免费视频,人人插天天干,久久91精品国产91久久

單項(xiàng)選擇題

The disinfection of various compartment in a vesel by filling them with a gaseous agents to destroy rats ect.means().

A.fire drills
B.washing and cleaning
C.fumigation
D.quarantine

微信掃碼免費(fèi)搜題