What major national-level development happened in the late nineteenth century?

There were many national level developments in the late-nineteenth century. Perhaps the most important was the development of the light bulb by Thomas Edison. Edison's invention revolutionized all aspects of American life ranging from work to leisure. It also inaugurated the modern electrical industry.

it would have concentrated power in the executive branch of the government. it would have restored balance among the three branches of government. it would have set a precedent for government intervention in the economy. it would have signaled an end to all the programs of roosevelt’s new deal.

did this .

i think the answer is   b.