A．(A) When we are touring around an opera house.

B．(B) When we are watching a TV series.

C．(C) When we are appreciating background music in a restaurant.

D．(D) When we are attending a lecture at college.

一学生上学途中被自行车撞倒，右颞部着地，当时昏迷达20分钟，醒后轻微头痛，四肢活动自如，次日感头痛加重，呕吐数次，伴嗜睡，来院就诊。首选的检查是（）

A.头颅CT

B.头颅MRI

C.脑血管造影

D.脑池造影

E.腰穿检查