--- Hey, Tom．I think I am quite familiar with these photographs．
--- It is impossible for anyone them before, because Mr．Newman had them developed today．
A. having seen
B. to have seen
C. to see
D. seeing
网友回答
A. having seen
(答案→)B. to have seen
C. to see
D. seeing
解析：考查非谓语动词。本题考查不定式的时态，根据句中时间状语before，故用其完成式，选B。