It’s D plz mark brainlyist
Assuming this is referring to the Greensboro sit ins, it started a chain of sit ins at restaurants. The 4 African American college students were the first to challenge the segregation inside restaurants. They sat in at one, which led to others being inspired and joining in by sitting in at other restaurants.
1.)To represent all of the people. if one branch had all of the power, there would be no way to keep them in control.
2.)to legislate and to represent the voters
3.) oversight function
hope this helps!