It Was Predicted in Harber's Study That the Positive Bias

It was predicted in Harber's study that the positive bias would be:

A) greatest in content-related feedback (subjective) to black essay writers.
B) greatest in mechanics-related feedback (objective) to black essay writers.
C) greatest in content-related feedback (subjective) to white essay writers.
D) greatest in content-related feedback (objective) to white essay writers.