Final answer:
HR professionals focused on an organization's culture and its development are known as Organizational development specialists. They operate within the field of organizational psychology, enhancing the workplace environment and productivity.
Step-by-step explanation:
HR professionals who understand an organization's culture and work to strengthen it are referred to as d) Organizational development specialists. Organizational development specialists focus on improving the interactions between employees, enhancing workplace culture, and subsequently boosting organizational productivity. They work within the domain of organizational psychology, which studies job satisfaction, motivation, leadership styles, and work-related social dynamics. These specialists are integral in shaping the organizational culture that involves the values, visions, norms, and interactions among the company's employees.