It __ and the streets were still wet.

A.rained
the streets were still wet.
因为说街道还湿着．（用的应该是现在时are）．
所以说雨下完了,如果用B雨一直下,那当然街道是湿着的．
但不过说,街道还湿着
这么说,已经暗示下完了．
用has rained 或rained 都行．