Question

how did john d. rockefeller vertically integrate his monopoly in 1882? he purchased iron mines around the country to add to his business. he purchased coal plants around the country to add to his business. he created a trust that controlled ninety percent of the nations oil refineries. he created a trust that controlled oil wells, refineries, and distribution networks.

Explanation:

Vertical integration involves controlling different stages of the production - distribution process. Rockefeller's trust controlled oil wells (production), refineries (processing), and distribution networks, which is a classic example of vertical integration. The other options are either not related to the oil - industry vertical chain (purchasing iron mines or coal plants) or only cover part of the process (controlling just refineries).

Answer:

He created a trust that controlled oil wells, refineries, and distribution networks.