糖皮质激素免疫抑制作用的机制是（）

A.抑制巨噬细胞吞噬功能

B.稳定溶酶体膜

C.增强心肌收缩力

D.使细胞内cAMP明显升高

E.直接扩张支气管平滑肌

— They haven''t finished the work up to now .

— Well , he ____ .

A．should have

B．should

C．ought to

D．ought have