What document specifies the composition of the governing body and the purpose of a corporation?

The correct answer is the articles of incorporation. This document is fundamental in establishing a corporation's existence and lays out crucial details, including the composition of the governing body (such as the board of directors) and the primary purpose of the corporation. It serves as the foundational legal document required by the state for the formation of a corporation, detailing essential elements such as the corporation's name, duration, purpose, and the number and types of authorized shares of stock.

Bylaws are indeed important for a corporation, but they primarily govern the internal management and procedural rules of the corporation after it has been formed. They outline how the company will be run, but they do not specify the structure or purpose of the corporation itself.

Guidelines and policies typically relate to internal practices and operational procedures but do not serve the formal role of establishing the corporation's legal framework or governance structure. Therefore, the articles of incorporation is the pivotal document that fulfills the requirements of specifying the governing body and the purpose of the corporation.