Final answer:
A violation of AICPA's ethical standards is least likely with a CPA basing the purchase price of a practice on a percentage of future fees. Other options involve clear conflicts of interest or misrepresentation, which are more likely to lead to ethical violations.
Step-by-step explanation:
A violation of the AICPA Code of Professional Conduct's ethical standards is least likely to occur when option A is chosen: a CPA purchases another CPA's accounting practice and bases the price on a percentage of the fees accruing from the clients over a three-year period. This is a commonly accepted practice and does not inherently involve any conflicts of interest or violations of ethical standards. In contrast, option B involves a direct conflict of interest, as the CPA could potentially be influenced to act in their own financial interest rather than those of their audit clients. Option C includes a conflict of interest that can impair objectivity, as the CPA is referring clients to a business they own. Lastly, option D could be misleading and suggest a partnership where none exists, which can violate ethical standards related to misrepresentation.