I hear they've promoted Tom, but he didn't mention _____ when we talked on the phone. [ ]

A. to promote

B. having been promoted

C. having promoted

D. to be promoted

细菌染色的基本程序为（）.

A.涂片-染色-干燥-固定

B.涂片-染色-固定-干燥

C.涂片-干燥-固定-染色

D.涂片-固定-染色-干燥

E.涂片-固定-干燥-染色