Final answer:
The correct leadership approach that changes styles based on different situations is the Contingency theory of leadership.
Step-by-step explanation:
An organizational leader who changes his leadership style based on the particular circumstances of a situation is practicing the Contingency theory of leadership. This theory posits that there is no one best way to lead a company and that an effective leadership style adapts to the changing conditions, tasks, and individuals involved. It contrasts with other styles like the Trait theory of leadership, which focuses on specific attributes that leaders have, Data-based leadership, which relies on data analysis for decision-making, and Nepotism leadership, where leadership opportunities are ascribed based on familial ties rather than individual skills or situations.