Final answer:
The fundamental question in ethics is what criteria to use when measuring the moral value of a particular act. Normative ethics focuses on establishing criteria or principles for identifying correct behavior. Consequentialist, deontological, and virtue ethics are three approaches to normative moral theory based on different criteria for determining moral conduct.
Step-by-step explanation:
The fundamental question in ethics is what criteria to use when "measuring" the moral value of a particular act. Normative ethics focuses on moral behavior and attempts to establish criteria or principles for identifying norms and standards to guide correct behavior. There are three main approaches to normative moral theory: consequentialist, deontological, and virtue ethics, each differing based on the criterion used for determining moral conduct.