The correct answer is D) members represent geographical areas.
According to the chart, the House and Senate are similar in that members represent geographical areas.
Here we are talking about one of the branches of the federal government: the legislative. The other two branches are the judicial (the Supreme Court) and the Executive (the President of the US).
As part of the legislative branch, the House of Representants and the Senate are part of the US Congress, the branch that creates and proposes laws in the country. Members of both houses represent geographical areas of the nation and are elected by citizens.