Which of the following is the best definition of the checks and balances principle in the U. S. Constitution?
The power is shared between the national and state governments
People have rights, liberties, and privileges
The people have the right to vote and change the government if it abuses their
power
Each branch has certain controls over the other two to prevent abuse of power

Each branch has certain controls over the other two to prevent abuse of power

Explanation:

The Checks and Balances principle goes hand in hand with the principle of Separation of Powers in the U.S. Constitution which divides the powers of the Federal Government into 3 branches being the Legislative, the Judiciary and the Executive.

This brings checks and balances to the powers that the various branches have as the branches will have powers that may override the powers of another branch if it is deemed that the overridden branch is abusing its mandate.

For instance, Congress (Legislative) may have the power to pass laws but if the President (Executive) does not assent to it, the law will not go into effect.

Another instance is how the Supreme Court (Legislative) can declare Executive orders unconstitutional but the same Executive branch gets to nominate the members of the Supreme Court.

b)

it created free trade throughout the colonial territories.