NPPE materials define ethics as the systematic study of moral principles, values, and conduct that govern individual and professional behavior. Ethics addresses questions of right and wrong, good and bad, fairness, responsibility, and integrity. In the professional context, ethics provides the foundation for Codes of Ethics that guide engineers and geoscientists in making decisions that protect the public, clients, employers, and the profession.

Option A correctly identifies ethics as the study of morality. NPPE references consistently use morality as the core concept underlying ethical reasoning, emphasizing moral judgment, ethical decision-making, and professional responsibility.

Option B is incorrect because history concerns past events and developments, not moral principles. Option C is incorrect because duties are obligations derived from ethical frameworks but are not themselves the study of ethics. Option D is incorrect because laws are rules enforced by the state, whereas ethics often go beyond legal requirements and may impose higher standards of conduct.

NPPE materials stress that ethical obligations may exist even when no legal rule applies and that professionals must act ethically, not merely legally. Therefore, option A is the correct answer.