Question

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

Explanation:

Vertical integration involves controlling different stages of a product's production/distribution. Rockefeller's Standard Oil used a trust to control oil wells (production), refineries (processing), and distribution networks (delivery) – this covers multiple stages of the oil business. The other options: controlling 90% of refineries is horizontal integration (same stage), and purchasing iron mines/coal plants are unrelated to oil's vertical stages.

Answer:

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