The correct answer is C, Marketing Manager.
In large organizations, there are heads over each department. These heads of the departments are responsible for taking every decision regarding their department. If there is such a decision in which the approval of the owner of the organization is required, then the owner is involved. Otherwise the head of the concerning department takes decision related to his department and reports to the head of the company over him.
So Marketing plans are approved by the Marketing Manager in large organizations.