Race was one of the variables. Aggression seems to be measured along the x-axis. Aggression to the left, over-protection to the right, judging by the lables on the graph. Aggression was one of the variables. Performance seems to measured along the y-axis, with optimal performance at the top, minimal performance at the base line.
Performance seems to be one of the variables.
All of the above would be the best answer choice, since the graph indicates that all of the above variables were measured. I don't have the slightest idea. I don't have a clue. There are no indications of how anything was measured. The graph is gibberish, and what that tells me is that this person has completely misunderstood the basic concepts of statistics.