A Problem with Recognizing the Right to Prevent Harm to Another

A problem with recognizing the right to prevent harm to another as a defense is

A) determining the category of assailants who can be stopped,and identifying situations in which the persons defended are strong enough to defend themselves.
B) determining the category of crimes that should be prevented,and identifying situations in which the assailants should be treated with lethal force.
C) determining the ways in which police could better handle the situation,and identifying situations in which the assailant's rights could be violated.
D) determining the category of persons who can be assisted,and identifying situations in which the person defended did not have a legal right to act in self-defense.