Papa John's hired Sam to work as a delivery driver. After Sam has endured a day of dealing with rude drivers, and when Sam is on his way to make his last pizza delivery, Bruce cuts Sam off and slightly dents his car. Sam loses it, pulls Bruce out of his car, and beats him senseless. Who is liable for Bruce's injuries?

Group of answer choices

Papa John's, under the doctrine of direct liability.

Both Papa John's and Sam, since principal and agent are both responsible for the agent's torts.

Sam only, since he was not acting within the scope of his employment.

Neither Papa John's nor Sam since Bruce instigated the incident and will not be successful in the lawsuit.