Answer: A. Enforce law, treaties and court orders.
Explanation: The constitutional power vested in the president of a nation is called the Executive power. As the Executive, the president is charged with and responsible for enforcement of law agreed upon by the congress.
The president as the chief Executive also takes up diplomatic task by negotiating with other countries on issues relating to trade, security, international cooperation and signs treaties.
The chief Executive also ratifies court orders and judgement on judicial pronouncement.
