— I dropped in at your house at about ten last night, but you weren't in. 

— I ______ regular exercises at the club. [ ]

A. did                        

B. was doing

C. had done                  

D. have been doing

老年，急性发病，眩晕，视物旋转，反复呕吐。血压220／120mmHg，眼震（+），听力（-），四肢肌力5级，病理征（-），最可能的诊断是（）

A.脑出血

B.脑梗死

C.前庭神经元炎

D.椎-基底动脉供血不足

E.梅尼埃综合征