Final answer:
The principle stating that each subordinate reports to only one supervisor is known as Unity of Command. It is a key aspect of organizational hierarchy and ensures clear lines of accountability and communication.
Step-by-step explanation:
The principle that states that a subordinate has only one supervisor to whom he or she is directly responsible is called the Unity of Command. This concept is a part of the hierarchy of authority within an organization, and it is essential to ensure a clear line of responsibility and accountability. By following Unity of Command, employees at all levels, from a shift manager at Walmart to a CEO, know who they are to report to and who will provide them with direction and feedback on their tasks. It simplifies communication and minimizes confusion about who is in charge of what, thereby reinforcing an orderly chain of command.