Answer:
The Greensboro Four contributed by using the sit-in method to incite social change.
Explanation:
The Greensboro Four refers to a group of four African American men who protested the segregation policy at a Woolworth's lunch counter during February of 1960. Initially, this started off as a small effort by these four to change the companies policy about refusing lunch service to African American citizens. However, after only a few days, hundreds of other colleged aged students joined in this sit-in movement.
This was an example of a nonviolent protest that African Americans used during the 1960's to incite change. These sit ins were then used in several different states all over the US. After roughly 6 months, the strategy was successful. Woolworth's reopened and allowed service to black and white citizens at their lunch counters.
B. The emergence of polished stone tools caused the emergence of agriculture
The US assumed global responsibility for containing communism because they emerged as a global superpower after World War II.
After World War II, many countries in Europe were ruined due to the amount of fighting that took place in their countries during the war. The US, however, did not have any of the fighting take place in the continental US. This lack of damage and a strong economy allowed the US to help other countries during this time.
It should be A. Each worker can focus on 1 thing that they are specialized in. Hope this helps