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

Read the following passage and answer the question.
On Monday, an urgent meeting was called by administrative head of ABC Ltd. The company has been witnessing various problems such as wastages of resources, ambiguity in transfer of information and inefficient Administration. Thus, organisational restructuring was need of the hour. The HR manager stated that "'the company needs to specify relationship between people, work and resources." Thus suggest an organisational structure based on the similar functions performed. Whereas marketing manager is of the opinion that company should be structured based on product line of the company. The meeting went for an hour and adjourned for next Monday and both the managers were called with valid justification for their claims.