Which Is True About Modern Presidents and Institutional Power

Which is true about modern presidents and institutional power?

A) Presidents are delegating too many constitutional powers to Congress,thus weakening their own institutional powers.
B) Presidents get the "last-mover" advantage,which increases their institutional power.
C) Presidents are increasingly institutionally powerful because they have more legal ability to act unilaterally.
D) Presidents' recent uses of executive orders and agreements have been ruled unconstitutional,decreasing the institutional power of presidents.