Question

when jacob riis published how the other half lives in 1890, the u.s. census bureau ranked new york as the most densely populated city in the united states... disease, sanitation, garbage and hygiene issues were constant concerns in crowded impoverished... districts, where vital statistics were alarming. jacob riis wrote frequently to urge measures to protect public health and to alert wealthy residents of the city to slum conditions that put everyone at risk.
—\jacob riis: revealing how the other half lives writer,\ library of congress, www.loc.gov (accessed october 17, 2017)
which issue was discussed in the writings of jacob riis?
discrimination against african americans in u.s. cities
harsh conditions of tenement housing in u.s. cities
growing conflict between rural regions and u.s. cities
increasing efforts to reduce chinese immigration to u.s. cities

Explanation:

The text mentions "crowded, impoverished... districts", "garbage and hygiene issues", "slum conditions" which all relate to the harsh living conditions in tenement housing. The other options (increasing efforts to reduce Chinese immigration, growing conflict between rural regions and U.S. cities, discrimination against African - Americans) are not mentioned in the provided text.

Answer:

Harsh conditions of tenement housing in U.S. cities