It was _____ that caused him to serve dinner an hour later than usual.

A．we being late

B．our being late

C．we were too late

D．because we were late

快速生长分支杆菌体外抗菌药物敏感性试验方法（）

A.纸片扩散法

B.E-test试验

C.琼脂纸片洗脱法

D.微量棋盘稀释法

E.绝对浓度法