请教几道题?1、-where did you get to know her? -It was on the farm_

请教几道题?
1、-where did you get to know her?
-It was on the farm____we worked.
A.that B.there C.which D.where
2、the river,____the bank is covered with trees,is very long.
A.whose B.which C.of which D.which of
3、Is this factory ____ the reaserchers work in.
A.where B.that C.in which D.the one
答案：D C D
详细解释一下