Answer:
In How the Other Half Lives, Jacob Riis exposed <u><em>the harsh living conditions in New York City slums</em></u>.
Explanation:
Jacob Riis' book "How The Other Half Lives" is a study of the squalid and <u>harsh living conditions of tenants in the slums of New York</u>. This documentary study of New York's slum areas through prose and photographs gives a different eye-opening window to the lives of the slum dwellers.
Through pictorial presentations and prose, Riis presents the poverty-stricken conditions of the city's poor in the slum areas. And through his documentary, the conditions of housing in the working class, as well as others, began to be reformed. His work also brought about the "muckraking" form of journalism where journalists report and expose societal issues.
Thus, the correct answer is the fourth/ last option.
