In this scenario, the police officer is faced with a situation where a man is actively attacking a woman. Under typical use of force regulations in law enforcement, the officer is generally justified in using a level of force necessary to stop the active assault and protect the victim.
Given the circumstances, the most appropriate option would be:
The officer can use moderate/limited force. This is very limited use of physical force to physically restrain the man. OC spray can also be used to subdue the attacker.
This allows the officer to intervene effectively to stop the assault while adhering to the principles of proportionality and necessity in the use of force. The use of less lethal options, such as OC spray or physical restraint, is typically encouraged to minimize the risk of injury to all parties involved. Deadly force would not be warranted unless there was an imminent threat to life or serious bodily harm to the officer or the victim.