— Is the meeting held in Room 302 or 303?

— It should be 302.But I hear that it________till tomorrow.[      ]

A. was put off 

B. will put off

C. has been put off  

D. is put off

下述哪项不是主动脉瓣关闭不全的体征

A．心浊音界呈靴形

B．主动脉瓣区或主动脉瓣第二听诊区可闻及叹气样杂音，向心尖传导

C．水冲脉

D．毛细血管搏动

E．GrahamSteell杂音