The unbroken line of authority that extends from the top of the organization to the lowest echelon and clarifies who reports to whom is termed

Chain of Command

Explanation:

Chain of Command  is the term of organizational field which depicts about the hierarchy of organization from lowest level to highest level. This order is established to maintain clarity about who is accountable to whom .

This also states about duty of a person to whom he/she has to report in the hierarchy. This pattern displays authority line/queue and who is answerable to who in organizational level. Power of decision making is maintained through the chain  

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