7. our government has a system of and that allow each branch to limit the actions of the other two branches. for example, the branch can enact a law, but the branch can veto that law.

Our government has a system of checks and balances that allow each branch to limit the actions of the other two branches. For example, the   legislative branch can enact a law, but the executive branch can veto that law.

Explanation:

The founding fathers of the U.S Constitution established the government in such a way that the three branches that are judiciary, legislative and executive have distinct powers. These branches need to cooperate for the enactment of laws. Therefore it ensured that no one branch get absolute powers and there were checked by the other branches ensuring the principle of separation of powers.

i would say b. research typically uses a variety of sources