关于where 和 in which

关于where 和 in which
xiamen,fujian province,is a beautifui city,___i paid a two-day visit during the spring festival.
A.which B.where C.to which D.in which
为什么只能用to which,为什么不能用where,非限制性定语从句中只能用where吗
She went to the company ____ he is working,
这个句子.where，in which 都能用。那上面那个为什么不行

visit to someplace是固定搭配,这里是一个非限制性定语从句,所以要把to提前,答案是C.当从句后面不缺成分时,可以用where
因为上面那个句子缺宾语,所以必须用Which充当宾语成分,而下面那个句子不缺成分,所以可以两个都用