The correct answer is The company controlled every step of steel production, from raw materials to distribution.
Andrew Carneige was a famous business man in America during the Gilded Age. His greatest success dealt with Carneige Steel. Besides owning the steel factories in Pittsburgh, Carneige also had control over the means of transportation, the raw materials themselves, and the businesses he interacted with. This is known as vertical integration.
Vertical integration is when one business controls all of the factors involved with developing and selling their good/product.