Frederick Douglass's primary purpose in writing "What to the Slave is the Fourth of July?" was to persuade readers about the unjust treatment of Black people, contrasting the celebrations of independence with the reality of slavery. He aimed to challenge his audience's conscience and inspire action against social injustices. Therefore, the correct answer is A: to persuade readers about the unjust treatment of Black people.
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The primary purpose of Frederick Douglass's speech is to persuade readers of the unjust treatment of Black people in America. He contrasts the celebration of Independence Day with the reality of slavery faced by millions. Douglass aims to challenge his audience's conscience and call for social change. ;