Final answer:
The increase in population in Great Britain and the movement of farmers to cities were caused by the Industrial Revolution.
Step-by-step explanation:
The increase in population in Great Britain and the movement of many farmers to cities were primarily caused by the Industrial Revolution. The Industrial Revolution brought significant changes to agricultural practices and technology, leading to increased agricultural productivity. As a result, fewer workers were needed on farms, pushing many farmers to seek employment in the growing factories and industries in cities.
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