What is the main idea of this excerpt from an article in the U. S. Constitution? OA. The Constitution establishes the executive branch as the most powerful branch of government. OB. The Constitution gives the president the power to select senators and representatives to serve in Congress OC. The Constitution creates the office of the president and establishes rules for how the president is to be elected. D. The Constitution creates Congress and establishes rules for how senators and representatives are to be elected.