Answer: A. Doctrine of executive prerogative.
Explanation: Doctrine of executive prerogative is the right afforded to the president of the United States by the constitution to act on his own. The doctrine of executive prerogative gives the executive power to the United States president to make certain policies or take certain decisions without congressional support or opinion. These decisions are usually attributed of issues of war or national emergency.
In the scenario above, the deployment of the the naval squadron to the Mediterranean sea to protect American merchant ship from barbary pirates by Thomas Jefferson without waiting for congressional approval exemplifies the doctrine of executive prerogative afforded to the president of the United States as it signifies an emergency issue required to safeguard the lives of the United States citizens
