Final answer:
The most common type of board in public organizations is an appointed board, where members are selected by an authority rather than elected, often to provide expertise or guidance.
Step-by-step explanation:
The most common type of board in public organizations is a(n) appointed board. Public organizations often require boards to govern and provide oversight. These boards can take various forms, depending on the legal framework and organizational needs. While elected boards are common in certain contexts, particularly within the commission system of county government where the governing body is elected by the public, appointed boards are widely used in various types of public organizations. Appointed boards are typically comprised of individuals selected by an authority, often within the government, and these members may or may not have legislative powers but provide guidance and support to the organization. The key aspect of an appointed board is that its members are not chosen through an electoral process but rather are appointed based on criteria set by the appointing authority, which can lend itself to a focus on specific expertise or affiliations.