Americans who opposed the constitution were called:

Anti-federalists

Explanation:

Anti-federalists were those who opposed the ratification of the Constitution. Anti-federalists supported this view for several different reasons. Many believed that the Constitution gave too much power to the federal government. They were fearful that this would dilute the successes of the Revolutionary War. Others were afraid that the autonomy of the individual states would be violated, or that the Constitution did not protect the rights of people sufficiently.

i am not 100% positive but i think it is is b. both are non-partisan jobs

i am pretty sure that members of congress have term limits, can be impeached, and are nominated through direct popular vote.