The correct answer is D. Divine Command Theory.
Explained briefly, a system of ethics is the collection of moral principles that affect how people make good decisions and lead their lives.
Utilitarianism, Humanism and Relativism are all collections of moral principles, ethical theories or stances. However, the theory of Divine Command is actually a meta-ethical theory based on the proposition that we do good based on what God commands us to do.
All other are considered to be systems of ethics.
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