Which of these explains one way that frederick douglass made his writing objective?
a. by using slang
b. by including vague descriptions
c. by avoiding sentimentality
d. by using few facts

One way that Frederick Douglass used to make his writing objective was by avoiding sentimentality. Option C is correct.

Objective language is employed in those writings which are intended to convey an accurate and fair message with reliable information. Therefore, in order to convey objectiveness, a writer will avoid bias, exxageration, and personal opinion.

Frederick Douglass was an American social reformer, abolitionist, orator, writer, and statesman.