What was the main pity for writing this letter

A. King hoped to explain why the discrimination of African Americans is immoral by giving specific examples of its harmful effects.

b. King attempts to encourage all Americans to end racism by joining the cause to defend civil rights for African Americans.

C. King sought to criticize white Americans who were supportive of his cause but who were too fearful of the Klan’s terrorism to take action to end racism.

D.King sought to respond to the criticism he received from people that he considered to be colleagues by methodically addressing each of their claims.