Manny coaches a team of 10-year-old boys in baseball. When they lost to their archrivals by a score of 7-2, the boys complained that the umpire was not fair and that they would have won if they had played on their home field. This is an example of ____.
a. ​correspondence bias
b. ​group-serving bias
c. ​just-world belief
d. ​self-serving bias