1.this is the place ____ last year.(A)

1.this is the place ____ last year.(A)
A.which i visited
B.where i visited
C.when i visited
D.in which i visited
2.Hangzhou ,______we spend last spring ,is one of the most beautiful cities in china.(A)
A.where
B.which
C.that
D.there
定语从句我站我的不是很好,这两题,我都不是很理解,能详细的说明一下每一项的能选不能选的理由好么?
还有这两题的区别是什么?