The correct answer is B) Jacob Riis.
The photographer, originally from Denmark, that became famous for taking pictures of the hardships that immigrants faced was Jacob Riis.
Jacob Riis (1849-1914) was a Danish photographer that published a book called "How the Other Half Lives," which was a collection of his photographs taken to show how immigrants and poor people lived in harsh conditions in the city of New York. His work made people think about this problematic situation and one way or the other, influenced future social reforms.