Which government system gives states most power federal
confederal
parliamentary
unitary

unitary

Explanation:

A unitary system has the highest degree of centralization. In a unitary state, the central government holds all the power. Lower-level governments, if they exist at all, do nothing but implement the policies of the national government.

a social contract.

"a social contract is an agreement between citizens and their leader where the citizens give up certain freedoms in exchange for protection. the constitution of the united states is an example of a social contract."