Answer:
A. checks and balances.
Explanation:c
The US Constitution is based on the Separation of Powers principle, which divides the government power and responsibility into the executive, the judicial and the legislative branches, and which also sets the basis for the Checks and Balances principle, a system whereby all three branches can oversee, influence, control and limit the other to prevent abuses of power and unbalance. The selection of federal judges by the President, the head of the executive branch, is an example of how this system works. However, this process does not stop here, once a federal judge is nominated, then it has to be approved by Congress in order to become a judge. This way, all three branches are involved in this process.
