这个句子的时态是（）。I have been looking for my lost book for three days, but I still haven’t found it.

这个句子的时态是（）。I have been looking for my lost book for three days, but I still haven’t found it.
A.现在完成时
B.现在进行时
C.现在完成进行时
D.过去完成时
正确答案：现在完成进行时