The article states:
In the first half of the 20th century, Dr. Bethune proved herself an inexorable force for enlightenment and equality, especially for Black women. In a time when the educational and vocational opportunities for Black Americans were sub-par…she used her considerable talents for organization and amity to change the social and political calculus on a national level, earning herself the title "First Lady of the Struggle."
Which is the closest synonym for the word inexorable?
elusive
resolute
affable
tolerable