Final answer:
Upton Sinclair was a muckraking journalist who exposed the horrible conditions in New York's slums and the meatpacking industry. His work led to reforms and improved workers' rights.
Step-by-step explanation:
Upton Sinclair was a muckraking journalist who took photos of New York's slums and exposed the horrible conditions to the city's upper and middle class. His work, particularly his book The Jungle, played a significant role in bringing attention to the unsanitary conditions in the meatpacking industry. Sinclair's efforts helped spark reforms and improve workers' rights in the early 20th century.
Learn more about Upton Sinclair and his impact on workers' rights