What year did the Great Chicago Fire occur?

The Great Chicago Fire occurred in 1871, making this the correct answer. This major event in history lasted from October 8 to October 10 and resulted in a significant portion of the city being destroyed, along with the deaths of hundreds of people and the displacement of over 100,000 residents. The fire is often attributed to a combination of dry conditions and wooden structures common in the city at that time.

Other years provided in the options do not correspond to the actual date of the fire. For instance, 1870 occurred a year before the fire, while 1872 and 1873 are both subsequent years, during which the city was already in the process of rebuilding. Thus, 1871 stands out as the pivotal year marking this catastrophic event.