In Which Situation Would an Emergency Room Nurse Be Justified

In which situation would an emergency room nurse be justified in proceeding without obtaining consent, verbal or otherwise?

A) An unconscious, profusely bleeding victim is brought in by ambulance.
B) A 13-year-old child is brought to the emergency room after suffering a fractured arm while at school.
C) A construction worker comes into the emergency room to have a boil lanced.
D) A 15-year-old high-school girl comes in for treatment of psoriasis.