Final answer:
The most severe penalty for violating the AICPA Code of Professional Conduct is revoking the CPA's membership in the AICPA, which ends their association with the professional body.
Step-by-step explanation:
The most severe penalty that may be imposed against a CPA for a violation of the AICPA Code of Professional Conduct is D. revoke the CPA's membership in the AICPA. While suspending a member's license to practice as a CPA or imposing fines and sanctions can be serious, these actions do not end membership.
Revocation of membership in the AICPA is the most extreme sanction and effectively ends the individual's formal association with the professional body representing Certified Public Accountants in the United States.
The most severe penalty which may be imposed against a CPA for violation of the AICPA Code of Professional Conduct is to revoke the CPA's membership in the AICPA.
Therefore, the corret option is D. revoke the CPA's membership in the AICPA.