Although we hadn't met for 30 years, I recognize him the minute ____I saw him.
A. when B. as C. that D while
也就是A选项。
再举一个表示地点的例子
Do you remember the house where we lived last year?
和
Do you remember the house which we built last year?
第一个句子,关系词做的是从句的地点状语,去年我们住在那所房子里。We lived in the house last year. 第二个句子中,关系词在从句中做built的宾语,我们去年盖了那所房子。We built the house last year.
有了这两个例子是不是更明白了