The correct answer is the executive branch.
The executive branch of the federal government consists of the presidency and their cabinet. During FDR's presidency, he greatly increased the power of this branch. He did this through domestic program called the New Deal. The goal of the New Deal was to help the American economy recover from the Great Depression. In order to do this, FDR made more federal government programs than any other president before him. This includes ones we still see today like the Social Security Administration and the Securities and Exchange Commission.