What is “D” in “ADKAR Model of Change” developed by Jeff Hiatt?

Read the following passage and answer the next 3 question  Organizational change refers to the actions in which a company or business alters a major component of its organization, such as its culture, the underlying technologies or infrastructure it uses to operate, or its internal processes. Organizational change management is the method of leveraging change to bring about a successful resolution, and it typically includes three major phases: Preparation, implementation, and follow-through. Source: - Harvard Business School Online