The above system of United States Constitution is showing three organs of the state i.e Legislative branch, Executive branch and the Judicial branch.
And below each division, their works are given. Aswecan were that, each of the organ is at same height which shows that they are practicing equal powers and they don't interrupt in each others work.
They practice the system of <u>Checks</u><u> </u><u>and</u><u> </u><u>Balances</u> to ensure that none of the organ is enjoying and grabbing too much.
So, the most appropriate option is:

Checks and balances system.
And, we are done !!
#CarryOnLearning...
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Not sure if you still need this, but it is actually the last once, the Channel and Sea were barriers that made it impossible to get an invasion force to the Island without the RAF and the Royal Navy interfering
Hello!
There are many ways citizens can participate in the election process. Citizens can vote in the election, campaign for the election candidates, work with groups of interest, sign petitions, create petitions, and more. =)