I didn’t know that you were at home. I didn’t drop...

Câu hỏi: I didn’t know that you were at home. I didn’t drop in. 

A Not knowing that you were at home, but I still dropped in.

B  I didn’t know you were at home although I didn’t drop in.

C Not knowing that you were at home, I didn’t drop in.

D If I knew that you were at home, I would drop in.