He said that his friend ______ there three days before, but she was not there_______.

A．had been; now

B．has been; then

C．had been; then

D．was; now

有关颈动脉内膜切除术，下列叙述错误的是（）

A.硬化斑块多位于颈总动脉分叉处

B.超过乳突尖一下颌角连线以上的病灶，颅外手术不可到达

C.腔内径狭窄50%即应手术治疗

D.双侧颈动脉狭窄，先做无症状的一侧

E.一侧狭窄，对侧闭塞，只做狭窄侧手术