It depends on the country in question
The Secretary of Defense
secretary of defense
Secretary of defense
The Senate must approve the heads of the cabinet departments.
The Senate has to approve the President's choices for "cabinet positions," that is, the heads of Executive branch departments. The President does have the authority to temporarily appoint a cabinet position without approval, if the Senate is not in session; that's called a "recess appointment." Recently, we had an interesting thing: the President appointed a cabinet position at a time when he said the Senate was not in session, and the Senate said they were.
The president has the authority to appoints members of the cabinet.
The Senate
The Senate must approve the president's cabinet.
senate
The US Senate must approve or disapprove such appointments.
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The Senate has the power to approve or consent to the appointment of an individual a president nominates to be a member of the Cabinet. However, it has no authority to fire that individual once confirmed. Only the President can fire a Cabinet member. While Congress has no power to fire a Cabinet member, Congress it does have the power of the impeachment process to remove, not fire, the Cabinet member. Grounds for impeachment and removal of a Cabinet member are the same as those for impeachment and removal of the President.