.....................is responsible for implementing and controlling the plan and strategies developed by Senior most executive.

Middle Management

The correct answer is option 2- Middle Management.

Middle Management is the link between top and lower level managers. They are subordinate to top managers and superior to the first line managers. They are usually known as division heads, for example production manager. Middle management is responsible for implementing and controlling plans and strategies developed by top management. At the same time they are responsible for all the activities of first line managers.