When should I use あそこで / そこで?


I have the sentence from 合格できる、日本語能力試験N２:

> 私は外国旅行をするたび、「 」専門の勉強をしている日本人の若い学者に会うと、思いがけない収穫をえる。

The choices for the blank are A）あそこで B）そこで C）ここで D）どこかで

I narrowed it down to either A or B, but then I realized that I don't know the
difference between them. Would someone mind explaining when either should be
used and the difference they make?




Here, you want an anaphoric usage of demonstrative pronoun, not a deictic one.
I think only ここ and そこ allow anaphoric usage.




Here, you want an anaphoric usage of demonstrative pronoun, not a deictic one.
I think only ここ and そこ allow anaphoric usage.

