How do historians define the modern era?

a. the period in world history that began after the end of world war ii

b. the period in history when people first became capable of communication

c. the period of world history that began after the end of the middle ages in europe

d. the present time period, in which people share information using technology

How did the cleveland massacre impact standard oil in 1872? standard oil hired all the laborers who were nearly killed during the cleveland massacre. standard oil became a monopoly in the cleveland oil market after the cleveland massacre. standard oil was bought out by other companies in the city after the cleveland massacre. standard oil closed down to avoid additional violence in the wake of the cleveland massacre.