The correct answer is A) Both have elected leaders and a bicameral legislature, but only the United Kingdom has a monarch.
In the United Kingdom, the government is a constitutional monarchy with a parliamentary system; it has a monarch (the King or Queen) as the head of state and a bicameral legislature consisting of the House of Commons and the House of Lords. In contrast, the United States has a democratic republic system with an elected president as the head of state and a bicameral legislature made up of the House of Representatives and the Senate, but it does not have a monarch.