When the minister came to the snow-stricken area, he was happy to see the disaster victims well_____．

A．take care of

B．took care of

C．taken care of

D．taking care of

计算机病毒是一个程序，或一段可执行代码，它的特点是（）

A、非授权可执行性

B、隐蔽性和传染性

C、潜伏性和可触发性

D、表现性或破坏性