When the National Government Gives the States Money to Entice

When the national government gives the states money to entice them to change state laws to match national goals or policies established by Congress, such as what happened with the Affordable Care Act and the expansion of Medicaid, it is an example of what?

A) the federal government exercising the national supremacy clause
B) dual federalism
C) the federal government acting through its implied powers in the U.S. Constitution
D) coercive federalism
E) police powers