We have helped the animals in danger __________ it has still a lot of things to do.[ ]

A. so

B. and

C. but

D. /

有传染源存在时对其排除的病原体可能污染的环境和物品及时进行的消毒称为（）。

A、终末消毒

B、随时消毒

C、预防性消毒

D、疫源地消毒