一般来讲,保险经营活动的起点是()。
A.保险展业
B.业务承保
C.确定
D.价格保险理赔
参考答案:A
This machine _____. It hasn't worked for years. [ ]
A. didn't work
B. wasn't working
C. doesn't work
D. isn't working
主动攻击可分为伪装、______、消息篡改、拒绝服务和分布式拒绝服务5类。