What term describes a multifamily urban dwelling that is typically overcrowded and unsanitary?

The term that describes a multifamily urban dwelling that is typically overcrowded and unsanitary is "tenement housing." Tenements emerged in the late 19th and early 20th centuries as cities expanded and there was a significant demand for affordable living spaces for the working class, especially immigrants.

These buildings were often constructed quickly and with minimal oversight, resulting in inadequate living conditions such as poor ventilation, insufficient plumbing, and overcrowded units. Tenements were commonly found in urban areas and became synonymous with the struggles of lower-income families during the industrialization of America. This historical context underlines why "tenement housing" is the correct term, as it directly reflects the social challenges associated with urbanization and housing standards at that time.

In contrast, an apartment complex refers to a group of apartments that are generally more organized and maintained than tenements. A brownstone is a specific style of townhouse often associated with more affluent neighborhoods. A condominium is a type of ownership rather than a type of housing structure, typically indicating that individuals own their units within a larger building while sharing common areas.