happy to meet you,Mr.smith.i ---to see you here.

happy to meet you,Mr.smith.i ___to see you here.
A.didnt think B.havent thought
C.am not thinking D.dont think
我觉得排除CD,请帮忙用时态方面说说.越详细越好.但拒绝长篇大论,无关紧要的copy的