Invested in barrels and warehouses to store oil.
a. cornelius vanderbilt
b. andrew carnegie
c. henry clay frick
d. john d. rockefeller

D. John D. Rockefeller.

Explanation:

Rockefeller (1839-1937) was deemed as one of the Captains of Industry.

In 1863 he started his career in the oil industry as a refiner, using his own savings. By 1870, he had founded the Standard Oil Company and was starting to purchase oil refineries in Ohio. He would even buy workshops that manufactured the barrels to store oil and warehouses to stock the barrels. All of his businesses were joined in the Standard Oil Trust of 1882.

the language dates from the contacts of arabian traders with the inhabitants of the east coast of africa over many centuries. under arab influence, swahili originated as a lingua franca used by several closely related bantu-speaking tribal groups.

when studying cause and effect, historians usually group the causes into different categories. for example, cultural causes reflect how a society’s literature and art convey the way the society saw itself in relation to the rest of the world. another resource that historians use to understand society is pop culture, which tells them the trends and ideas that are preferred by the common people. when studying cause and effect, it’s important to remember multiple causation, or the idea that an effect could have several causes and vice versa.  

the correct option is “cultural causes” since art and literature are related to the culture of a place. culture is determined by literature, art, music.

the correct option is “pop culture” since it reflects the likes and ideas of common people whereas the rest of the options do not focus on common people.  

the correct option is “multiple causation” since it refers to the idea that events are caused by multiple reasons, not just a single one.