What encompasses all activities involved in hiring and retaining workers?

The correct choice, which is staffing, covers all activities related to hiring and retaining workers. Staffing is a crucial aspect of human resource management that includes identifying job vacancies, recruiting candidates, selecting suitable individuals, and ensuring their ongoing development and retention within the organization.

This process is essential because it not only fills positions with qualified staff but also aligns the workforce with the organization's goals and culture. Effective staffing strategies contribute to organizational efficiency and employee satisfaction, which ultimately leads to reduced turnover and improved performance.

Management, while relevant in a broader sense, refers to overseeing and coordinating the activities of various resources including people, processes, and technologies within an organization. It is too general to encompass specifically the activities of hiring and retention.

Marketing relates to promoting and selling products or services and does not pertain to staffing or employee management.

Training involves developing employees' skills and knowledge after they have been hired, but it does not include the initial phases of hiring or retention strategies. Thus, staffing is the most accurate term for the activities described in the question.