The answer is A. Rockefeller was into big business and capitalism. Horizontal integration is merging two companies that serve the same purpose to get a monopoly on the market
Assuming you're asking "How was the era of thomas edison different than ours?" It was mainly different because the long-lasting ligh bulb had not been invented yet, meaning many people had to rely on candles.
End of the Great Depression thanks to the Japanese bombing Pearl Harbor. Most Americans got jobs during the war. The girls took over the men’s job.
