An organization's mission is the:

Comprehensive and Detailed in Depth Explanation:

An organization’s mission statement defines its fundamental purpose—why it exists and what it aims to achieve in the long term. It provides a clear direction for the organization’s activities and aligns employees with its core objectives.

Option A (Plan of action to achieve the goals of the organization): This describes a strategy or operational plan, not the mission.

Option B (Fundamental purpose of the organization): Correct, as the mission articulates the organization’s reason for being.

Option C (Shared beliefs of the people in the organization): This refers to organizational culture, not the mission.