Which of the following best describes self-defense?

The best description of self-defense is the use of force to prevent personal injury. Self-defense is a legal doctrine that allows individuals to protect themselves from imminent harm or violence. It is not simply about responding to an attack but about the necessity to act in a situation where personal safety is threatened. This principle is grounded in the idea of protecting oneself from harm, and the force used must generally be proportional to the threat faced.

The other options do not accurately represent the concept of self-defense. Retaliatory actions imply a response after an attack has occurred, which does not fit the definition focused on prevention. Verbal warnings might be a strategy in some scenarios, but they do not constitute self-defense as they lack the use of force needed to protect oneself physically. Lastly, the notion of legal permission to fight back regardless of circumstances contradicts the legal constraints of self-defense, which typically requires immediacy and proportionality to the threat at hand.