Final answer:
Susan B. Anthony was an advocate of women's suffrage who brought cases supporting women's voting rights to the Supreme Court.
Step-by-step explanation:
The most accurate statement to characterize the role of Susan B. Anthony in expanding voting rights is option B. Susan B. Anthony was an advocate of women's suffrage who brought cases supporting women's voting rights to the Supreme Court.
Anthony played a crucial role in promoting the cause of women's suffrage. She co-founded the National Woman Suffrage Association (NWSA) and worked tirelessly to secure a constitutional amendment granting women the right to vote.
While Anthony was instrumental in advancing women's rights, Option A is inaccurate as she focused primarily on women's suffrage and did not bring together advocates for African-American suffrage. Option C is also incorrect as she primarily championed women's suffrage and did not specifically use nonviolent civil rights tactics for African American suffrage. Finally, Option D is inaccurate because Susan B. Anthony's efforts were not unsuccessful. She played a significant role in the women's suffrage movement and her work eventually led to the ratification of the 19th Amendment in 1920.