Concept:Span of control refers to the number of subordinates a manager or supervisor directly oversees.
Explanation:The question asks for the term that describes the number of subordinates under one supervisor.
Option A, "unity of command," means each subordinate reports to only one superior.
Option B, "chain of command," is the formal line of authority from top to bottom.
Option C, "span of control," is the exact number of subordinates one supervisor manages.
Option D, "unity of direction," means one plan and one head for a group of activities.
Therefore, the term that matches the question is the span of control.
Answer:C. span of control