Final answer:
The nurse is using the ethical system of Utilitarianism, which focuses on maximizing overall happiness and well-being.
Step-by-step explanation:
The nurse is using the ethical system of Utilitarianism. Utilitarianism is a consequentialist approach that focuses on the consequences or effects of an act. It suggests that an act is morally right if it produces the greatest good for the greatest number of people. In other words, the nurse bases ethical decisions on maximizing overall happiness and well-being.