The correct answer to this open question is the following.
Although there are no options attached, we can answer the following.
One way in which robber barons such as John D. Rockefeller and Andrew Carnegie helped society was by creating jobs and making large donations, big sums of money to charity, and creating foundations to help people.
They did that because they were considered Robber Barons because
they were wealthy owners of the American Industries during the Gilde Edge. Two of the most famous Robber Barons were John F. Rockefeller, owner of the Standard Oil Company, and Andre Carnegie, owner of the Steel Company. But there were also others like Cornelious Vanderbilt and Henry Ford.
However, the presence of their huge companies resulted in the lack of competition in their industries. They grew by buying other companies to the degree they became monopolies that dominated the industry.
