Final answer:
Realist writers in the late nineteenth century worked on improving income inequality and urbanization challenges.
Step-by-step explanation:
The two social issues that Realist writers in the late nineteenth century worked to improve were Income Inequality and Urbanization Challenges. Realist writer Mark Twain focused on the issue of Income Inequality in his book The Gilded Age, where he co-authored with Charles Dudley Warner. He criticized the corruption and wealth disparities during the era of industrialization. Henry James, another Realist writer, tackled Urbanization Challenges in his works. He portrayed the struggles and complexities faced by individuals living in rapidly growing cities, highlighting the social and cultural changes brought about by urbanization.