The "us versus them" dynamics that characterize ingroup-outgroup dynamics become especially evident when the two groups

These differences become more stark when the two groups are competing for the same outcome (or similar outcomes). When there is something that is valued by both groups, any sort of small difference that can be pointed to and exacerbated will be and used against the out-group.

I believe it is A/1 hope this helps you!! (love your profile pic also)

Explanation: