Either you or one of your students___to attend the meeting__ tomorrow.

A．are; to be held

B．is；being held

C．is; to be held

D．are；having held

阮蛋白病的特点不包括（）

A.由阮蛋白（prion）引起

B.可以侵犯人和动物

C.具有种属屏障的特点

D.属于全身性系统性疾病

E.具有传染性