Which of the Following Was One of the Secrets of John

Which of the following was one of the secrets of John D. Rockefeller's success?

A) He paid attention to the minutest details and understood the benefits of vertical integration.
B) He pioneered a division of labor in which he concentrated on financial matters and delegated the technical operations of the industry to his managers.
C) He concentrated on the "big picture" and did not get bogged down in details.
D) He did not waste a lot of money on advertising.
E) He was willing to develop equal cooperative relationships with his competitors.