Final answer:
Susan B. Anthony was a key figure in influencing sociological thought in the United States through her work on women's civil rights and suffrage.
Step-by-step explanation:
Among the social reformers and thinkers who played a significant role in influencing sociological thought in the United States, Susan B. Anthony stands out as an eminent figure. Her work furthered the cause of women's civil rights, challenging gender roles and advocating for suffrage, thus shaping sociological discourse and reform movements in the U.S. Other key figures in reform movements like W. E. B. Du Bois also notably impacted sociological thought, especially concerning social justice and civil rights, with their focus on overcoming racial inequalities.