—One can't be happy without friendship.  

—You are right. As for me, I'll never forget the days ______ I spent with my best friend.    [ ]

A. that    

B. when    

C. who      

D. where

厚质防水涂料施工中，在天沟、水落口及板端缝处等特殊部位常采用涂料增厚处理，即刮涂一层（）厚的涂料，其宽度视具体情况而定.

A.1～2mm

B.2～3mm

C.3～4mm

D.4～6mm