The correct answer to this open question is the following.
The branch of government that I believe has the most power overall is the executive branch.
The President of the United States is the leader of the nation. He is the chief of the Cabinet and supervises many counselors in the White House. He is the Commander-in-Chief of the Armed Forces (Army, Navy, and the Air Force). He also is the Chief Diplomat of the country and has the power of veto laws. That is why I think the executive branch is more powerful than the judicial branch and the legislative branch.