Final answer:
Frederick Douglass showed his belief in freedom of conscience and expression by writing an autobiographical account of his life, speaking actively against slavery, advocating for equal rights for all, and defending the First Amendment.
Step-by-step explanation:
Frederick Douglass demonstrated his belief in freedom of conscience and expression through various significant actions. A) By writing and publishing his autobiography, Narrative of the Life of Frederick Douglass, an American Slave, he not only shared his personal experiences and thoughts but also advocated for the abolition of slavery and freedom of expression. This bold move, due to its content, forced him to flee the United States to avoid retribution. B) Through organizing and delivering electrifying anti-slavery lectures and participating in conventions, Douglass actively used his voice and platform to push for change. C) His advocacy extended to women's rights, emphasizing his belief in equal rights for all, regardless of gender or race. D) Additionally, by supporting the First Amendment and defending free speech and the freedom of the press, Douglass underscored his commitment to these fundamental human rights.