The passing of federal civil rights legislation in 1964 and 1965 did not mark the end of the civil rights struggle in georgia. many cities, including atlanta, experienced wide-scale race riots. which statement best explains why people were rioting?

Because of there race they did not agree with each other. that's why there were riots.

People are rioting because they are experiencing discontent and unrest from laws and implementations that are in their country. Basically, this starts from their welfare as citizens and as employees who would like to enjoy the fruits of their labor. They might have passed their threshold based on the uncontrolled situation which the government failed to address and they want an immediate solution for all of these concerns. 

The best bet is to google