Choice "C" is correct. The project manager is responsible for project administration on a day-to-day basis including identifying and managing internal and external stakeholder expectations.
Choice "d" is incorrect. Carrying out the work and producing the deliverables is a responsibility of the project members.
Choice "a" is incorrect. Interfacing between the organization and the project itself is a responsibility of the project sponsor.
Choice "b" is incorrect. Approving project deliverables is a responsibility of the executive steering committee.