—It is nearly six p.m. Will you have dinner here?

—Sorry, _______. I have many things to do.[ ]

A. I mustn't

B. I can't

C. I needn't

D. I don't

关于腹外疝的叙述不正确的是

A．是腹内脏器通过腹壁先天性或后天性缺损或薄弱区向体表突出，形成一肿块

B．病因有腹壁强度减弱或腹内压增加

C．按疝的内容物能否回纳分可复性疝、难复性疝

D．嵌顿性疝是指疝内容物突然不能回纳，发生疼痛等系列症状

E．绞窄性疝是指疝内容物发生扭转，发生一系列症状