Who is authorized to prescribe all rules and regulations under § 7805?

The correct answer is that the Secretary of the Treasury or their delegate is authorized to prescribe all rules and regulations under § 7805. This section of the Internal Revenue Code provides the Secretary with broad authority to enforce tax laws and ensure their proper implementation. It empowers the Secretary to create regulations that provide guidance on how tax laws should be applied, helping clarify the intentions of Congress in the legislation.

This authority is critical, as it allows for the development of detailed rules that can address a wide array of tax issues, covering everything from compliance to procedural requirements. The Secretary's ability to delegate this power further allows for flexibility and efficient governance in handling complex tax matters.

The other options do not hold this specific authority; for example, the President of the United States does not directly enact tax regulations, nor does the Chief Financial Officer have a role in this context. Similarly, the Board of Directors of the IRS does not have regulatory authority but instead manages the agency's operational policies and priorities. Thus, the Secretary of the Treasury remains the key figure for establishing tax regulations under § 7805.