Who produced large quantities of steel very efficiently by buying and controlling iron ore deposits, steel mills, and railroads?
a. andrew carnegie
b. jean lenoir
c. alexander graham bell
d. thomas edison

The correct option is:

A. Andrew Carnegie.

Andrew Carnegie (1835 - 1919) was a Scottish-American industrialist, business magnate, and philanthropist. He drove the development of the American steel industry in the late 19th century. By the 1860s he held investments in railroads, sleeping cars, bridges, and oil derricks. He built Pittsburgh's Carnegie Steel Company, and after selling it, he surpassed John D. Rockefeller as the richest American for a few years.

zheng he was a chinese explorer who lead seven great voyages on behalf of the chinese emperor. his seven total voyages were diplomatic, military, and trading ventures, and lasted from 1405 – 1433. however, most historians agree their main purpose was to promote the glory of ming dynasty china.

explanation:

its many islands, high mountains, and remote peninsulas isolated population centers.