— Are you still thinking about the email Tony sent you yesterday? 

— Oh, to tell the truth, that's _____ makes me feel excited. [ ]

A. What

B. how

C. that

D. why

下列细菌感染的典型症状是"里急后重"的是（）

A.小肠结肠炎耶尔森菌

B.大肠埃希菌

C.弗劳地柠檬酸杆菌

D.志贺菌

E.沙门菌