Correct answer: A. vetoing laws passed by Congress.
This is a significant power in the hands of the President. Congressional decision making is affected by the knowledge that in both houses of Congress, a two-thirds majority will be needed to override the President's veto. Historically, Congress has been able to override less than 10% of presidential vetoes. So Congress will seek to make sure they have sufficient votes before proceeding with passage of a bill into law ... unless they want to pass the legislation simply as a statement of principle, knowing they don't have the votes to override a veto.
