The correct answer is option 'D', i.e., The Governor of a State.

Explanation:
The Finance Commission is a constitutional body that reviews the financial position of both the Union and State Governments of India. It also recommends the distribution of tax revenues between the Union and the States and among the States themselves. The Finance Commission plays a crucial role in ensuring fiscal federalism and maintaining the financial equilibrium between the Centre and the States.

Constitutional Provisions:
The Finance Commission is constituted by the President of India every five years or at such intervals as he may deem necessary. The provisions regarding the Finance Commission are enshrined in Article 280 of the Indian Constitution. According to this article, the President shall constitute a Finance Commission within two years from the commencement of the Constitution and thereafter at the expiration of every fifth year or at such earlier time as the President considers necessary.

Composition and Functions of the Finance Commission:
The Finance Commission consists of a Chairman and four other members appointed by the President. The members of the Commission are selected from among persons who have had experience in public affairs, economics, or financial matters.

The functions of the Finance Commission include:

1. To make recommendations to the President as to:
- The distribution of the net proceeds of taxes between the Union and the States.
- The principles that should govern the grants-in-aid to the States from the Consolidated Fund of India.
- The measures needed to augment the Consolidated Fund of a State to provide for the devolution of the duties and powers between the Union and the States.

2. To assess the revenue deficit of the States and suggest measures to augment the Consolidated Fund of a State to bridge such deficit.

Authority to Constitute the Finance Commission for Panchayats:
While the Finance Commission primarily deals with the financial position of the Union and the States, the Constitution also empowers the President to constitute a Finance Commission for reviewing the financial position of Panchayats (local self-governments). This provision is mentioned in Article 243-I of the Indian Constitution.

According to Article 243-I, the Governor of a State shall, as soon as may be within one year from the commencement of the Constitution (Seventy-third Amendment) Act, 1992, and thereafter at the expiration of every fifth year, constitute a Finance Commission to review the financial position of Panchayats and make recommendations on:
- The distribution of the net proceeds of taxes, duties, tolls, and fees leviable by the State between the State and the Panchayats.
- The determination of the taxes, duties, tolls, and fees that may be assigned to the Panchayats.
- The grants-in-aid to the Panchayats from the Consolidated Fund of the State.

In conclusion, the Governor of a State is authorized to constitute a Finance Commission for reviewing the financial position of Panchayats as per the provisions of the Indian Constitution.