What what is true about the red summer of 1919

The term Red Summer was coined by author James Weldon Johnson, he was working as a field secretary of NAACP. Red Summer happened in the fall of  1919 when the white supremacists attacked the blacks in more than three dozen cities and one rural county. It led to the death of many black African-Americans. The blacks fought back in some of the cities. These attacks killed more than 200 black people. The riots were due to social tensions caused due to competition in jobs and housings during the postwar years. It was also feared that the riots were due to communist and socialist influence.

ok sorry the answer is a. by their religion