Answer:
IRS ,AICPA Statements on Standards for Tax Services.
Explanation:
From the question, we are informed about Bob, that has a client with a strong belief that he is correct about an aggressive but creative tax position.
and how Bob files the tax return with disclosure on his client's included.
In the case of agreement on the disclosure of the position, then it should be disclosed to IRS. which is a form of Statements on Standards for Tax Services.they are responsible for quality control as far as tax is concerned.