What Made Emmett Till's 1955 Murder in Mississippi Different from Previous

What made Emmett Till's 1955 murder in Mississippi different from previous racist killings of African Americans in the South?

A) This was the first time that a black teenager tried to advance the Civil Rights Movement.
B) Emmet Till was the youngest African American victim of racist violence in the United States.
C) Till's family decided to fight back by publicizing his battered body and speaking in court.
D) The jury failed to convict the accused murderers.