All of the following help to explain the President’s difficulty in controlling cabinet-level agencies EXCEPT:
A. Agency staff often have information and technical expertise that the President and presidential advisers lack
B. The President can only fire appointees before they have been confirmed by the Senate
C. Civil servants who remain in their jobs through changes of administration develop loyalties to their agencies
D. Congress is a competitor for influence over the bureaucracy
E. Agencies often have political support from interest groups

B. The President can only fire appointees before they have been confirmed by the Senate

Explanation:

The Appointments Clause confers plenary power on the President to nominate various officials. It also confers plenary power to the Senate to reject or confirm a nominee, through its advice and consent provision. This separation of powers between the President and Senate is also present in the treaty Clause of the Constitution, which gives international treaty-making power to the President, but attaches to it the provision of the Senate's advice and consent.

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