I guess we’ve already talked about this before but I’ll ask you again just .
A. by nature
B. in return
C. in case
D. by chance
网友回答
A. by nature
B. in return
(答案→)C. in case
D. by chance
解析：短语辨析。by nature天生地；in return 作为回报；in case以防万一；by chance偶然地，意外地。句意：我猜我们以前已经讨论过这个，但是为了以防万一我要再问你一遍。选C。