Why did millions of people move from rural areas to the cities to work?

As a consequence of the Industrial Revolution, which began in the 19th century in England, cities began to be created that centralized industries and the incipient technological poles. Thus, cities such as Manchester became true centers of production, which required a large amount of labor in order to maximize their industrial production and, therefore, their profits.

This encouraged the movement of millions of people from rural areas, in which they carried out a subsistence economy, to the cities, where they would enter the system of wage labor in industrial production tasks.

an unexpected salary cut

i would say your answer is a)

sorry if im wrong