How Does Political Power Function in the Modern State

How does political power function in the modern state?

A) Political power is centralized in the government,which may legitimately use force to regulate the affairs of its citizens as well as its relations with other states.
B) Political power is centralized in the government,which provides a constitution to determine political process.
C) Political power is vested in provinces or territories as democratic entities.
D) Political power flows from the hands of the voters who elect political representatives to carry out their will.