——What do you think of the speech given by the CEO from Hong Kong ?

——Excellent, I have never heard ______ one before.

A．a more interesting

B．the most interesting

C．a more interested

D．the most interested

中毒型细菌痢疾的发病机制可能是（）

A.细菌毒力强

B.细菌侵入量多

C.细菌侵入数量多且毒力强

D.特异性体质对细菌毒素呈强烈过敏反应

E.特异性体质对细菌的强烈过敏反应