Corporate governance is implemented through the formal frameworks that dictate authority, decision-making, and accountability. The overall organizational structure (e.g., hierarchical, matrix) is the primary mechanism that defines reporting lines, roles, and responsibilities throughout the company. Within this broader framework, specific bodies like the executive committee are created with a defined structure and charter to oversee strategic execution and key governance functions. Both are examples of structures designed to implement governance rules, making "All of the above" the most comprehensive and accurate answer.

A. This is a correct example, but it is incomplete as the overall organizational structure is also a fundamental mechanism for implementing governance.

B. This is also a correct example, but it is incomplete as specific committee structures are also designed for governance implementation.

1. Fama, E. F., & Jensen, M. C. (1983). Separation of ownership and control. Journal of Law and Economics, 26(2), 301-325. In Section 3.2, the paper discusses how the hierarchy of an organization, from the board of directors down, forms a system for decision control and implementation, which is a core function of governance. This supports that both the top committees and the overall structure are part of the governance framework. (https://doi.org/10.1086/467037)

2. Roberts, J. (2004). The Modern Firm: Organizational Design for Performance and Growth. Oxford University Press. Chapter 4, "Architecture and Structure," explains how the formal organizational structure, including the allocation of authority and the design of units and committees, is fundamental to implementing strategy and ensuring control and coordination (i.e., governance).

3. MIT OpenCourseWare. (2007). 15.225 Advanced Strategy. Fall 2007. Lecture 10, "Organizing for Innovation," discusses how different organizational structures (functional, divisional, matrix) create different systems of control, coordination, and incentives, which are the mechanisms through which governance policies are enacted. This establishes the direct link between the overall organizational structure and governance implementation.