THEY ________ GOOD PREPARATION BEFORE THEY ______ THEIR EXAM YESTER...

20. - KIEM TRA 1 TIET LOP 11 SO 1
KIEM TRA 1 TIET LOP 11 SO 1

20.They ________ good preparation before they ______ their exam yesterday.

A. made / had taken B. had made / took

C. have made / take D. will have made / have taken