Final answer:
The Industrial Revolution is most responsible for London's population surge as it led to job creation and urbanization, enticing people from rural areas to move to cities in search of work.
Step-by-step explanation:
The most responsible factor for London's surge in population is C. Industrial Revolution. The Industrial Revolution started in the 1770s and led to an upsurge in urbanization. Cities grew to accommodate a rapid influx of people who relocated from rural areas in search of work in the new factories and industries. The availability of jobs and the socioeconomic changes during this period brought about significant growth in urban populations, particularly in industrialized cities such as London, Birmingham, and Manchester.
While Warren's Blacking House, Debtor's Prison, and Puritan Parliament have historical significance, they did not directly contribute to the population surge as the Industrial Revolution did. The transformation of the British economy due to industrialization not only altered the landscape of urban living but also shifted population centers and redefined societal structures.