.

.Tim was late again， ______stayed up last night ,he would have come here earlier.

A If he didn’t  B Did he not C Had he not  D If had he not

下肢静脉曲张伴有深静脉阻塞者，选用的手术方法是（）。

A.大隐静脉高位结扎术

B.大隐静脉分段结扎术

C.大隐静脉剥脱及切除术

D.筋膜下交通支结扎术

E.以上都不是