Final answer:
Public accounting promotes ethical standards to establish expectations, ensure accountability, and maintain trust between accounting professionals and their clients.
Step-by-step explanation:
The best explanation for why public accounting, as a profession, promotes ethical standards and ways to ensure their observance is option C. Ethical standards are established so that users of accounting services know what to expect and accounting professionals know what behaviors are acceptable, and so that discipline can be applied when necessary. By having clear ethical standards, the profession maintains accountability and trust between accounting professionals and their clients, as well as within the profession itself.