Questions 26 to 29 are based on the passage you have just heard.

A．To help her husband to win the election.

B．To encourage healthy eating.

C．To call on people to be vegetarian.

D．To tell the kids that vegetables are delicious.

(8～9题共用题干)患者，张莱，男，35岁，既往风湿病史，超声检查二尖瓣及主动脉瓣回声增厚增强，二尖瓣口舒张期最高流速2．1m/s，主动脉瓣口舒张期可见中度反流血流信号。

该患者经瓣膜置换术后四个月复查，下列哪项为人工瓣膜功能异常的超声表现

A．二尖瓣位人工瓣瓣口舒张期峰值流速2m／s

B．主动脉瓣位人工瓣瓣口收缩期峰值流速2．5m／s

C．二尖瓣位人工瓣跨瓣压差22mmHg

D．主动脉瓣位人工瓣反流束面积2cm²

E．二尖瓣位人工瓣反流束面积1．8cm²