The key contribution that was the identification of the major functions of management which are planning, leading, organizing, and controlling is; Administrative management
Administrative Management is defined as a type of management that has to do with the management of every part of an organization.
Now, the administrative managers are responsible for planning, organizing, leading, controlling, and coordinating and stating the need for budgets and controls.
In conclusion, this type of management is basically one that seeks to make an organization more efficient.
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