Answer: B) the President to veto a bill passed by Congress
Explanation: The principle of Checks and balances in government may be explained as an idea of power segmentation which allows each arm of a democratic government including the executive, the legislative and the judiciary to have a certain amount of power and control over policies, laws and reforms of a country. This idea is especially useful in checking the excesses of a certain arm of government and ensures that other arms are able to come in when a certain arm of government step beyond it's bounds.
The president could veto a bill passed by Congress, because, bills are made and passed by the legislative or congress, however, the executive arm has the power to enforce or veto the bills.
