Final answer:
The middle-class in Europe benefited the most from industrialization during the 19th century, as they gained economic opportunities and improved living standards.
Step-by-step explanation:
In Europe, the group that benefited most from the industrialization of the 19th century was the middle-class. The middle class included the ranks of engineers, foremen, accountants, and bureaucrats necessary for building, overseeing, and running the new industrial and commercial operations that industrialization fostered. This class also enjoyed improved standards of living, with expanded opportunities for leisure and recreation such as libraries, theaters, and education, that included the creation of land-grant colleges which provided practical professional training relevant to their burgeoning professional roles.