SAT Question e31b0056: Form Structure And Sense answer and explanation

English - Form Structure And Sense - Subject Verb Agreement
0:00
FREE OFFICIAL BANK
Mary Madden of Ohio ______ a fierce advocate of women’s voting rights in the late 1800s. The dedication of Madden and her fellow activists was rewarded in 1920, when the Nineteenth Amendment to the US Constitution guaranteed American women the right to vote.
181
Difficulty:Easy
Which choice completes the text so that it conforms to the conventions of Standard English?