Final answer:
Martin Luther King Jr. was the president of the SCLC, an organization that supported the civil rights movement.
Step-by-step explanation:
Martin Luther King Jr. was the president of the Southern Christian Leadership Conference (SCLC). The SCLC was an organization led by black ministers who supported the civil rights movement. It was formed by King in 1957 and played a significant role in organizing protests and demonstrations advocating for racial equality.