When karen does poorly on a weekly test, she blames it on the distractions she had at school that week. in this scenario, karen is using the to justify her performance on the test?

The answer in the blank is self serving bias. It is because with the use of self serving bias, it enables an individual to point out excuses or facts about what happened in a positive way for the sake of their character or performance but it causes negative effects or events. It could be seen above as Karen blames distractions in which she attributes a positive even for her own sake but it still led to a negative effect in which she has low test performance.