what social forces intervened in the lives of john d. rockefeller, andrew carnegie, steve jobs and bill gates

Other business titans which might have created competition & fast-performing computer.

Explanation:

As regards John D. Rockefeller and those around his generation, it'll be competition created other businesses, while Bill gates and Steve jobs were aided by the growth of the internet, transformation of the computer system, especially when fast performing computers began coming out.

answer; ///i believe the correct answer is (b) the writing of the ancients who lived in india after the indus valley inhabitants died out;