The correct answer is B. The Industrial Revolution.
Step-by-step explanation
The Industrial Revolution was a period in which profound transformations occurred in different areas of the European economy, society, and technology (mainly Great Britain) since the 18th century. Once this revolution started, its impact was massive and it spread throughout Europe, and North America in the 19th and 20th centuries. These changes allowed for an increase in the European population because the displacement towards large industrialized cities was encouraged and the demand for labor for factories increased rapidly. Therefore, the correct answer is B. The Industrial Revolution.