In Phase 2 of Bandura, Ross and Ross' Study, Why

In Phase 2 of Bandura, Ross and Ross' study, why did an experimenter stop the children from playing with attractive toys after a couple of minutes?

A) It was necessary to mildly provoke them so that they would not be inhibited from displaying aggressive behaviour
B) The toys were expensive and the researchers did not want them to get broken
C) The toys were reserved for other children
D) The children needed a short activity between seeing the model and being observed for aggression
E) The researchers wanted to see if the children in the aggressive condition would be more likely to argue than the children in the other conditions