Final answer:
The Standards for Tax Services (SSTS) contain advisory guidelines for CPAs, enrolled agents, attorneys, and IRS authorities.
Step-by-step explanation:
The Standards for Tax Services (SSTS) contain advisory guidelines for CPAs, enrolled agents, attorneys, and IRS authorities. Therefore, the correct answer is e. All of the above. These standards provide guidance and requirements for professionals who provide tax services. For example, the SSTS may address issues such as confidentiality, competence, and due diligence when preparing tax returns or representing clients before the IRS.