Why did riots break out in dozens of american cities in the late 1960s

Monopolies were legal in the united states until a)the 1860s. b)the 1870s. c)the 1880s. d)the 1890s.

Interest groups representing businesses and investors are often among the most successful lobbying groups for all of the following reasons, except a. such groups have the financial resources to mount sustained campaigns on their own behalf b. these groups' members contribute heavily to many legislators' campaigns and in so doing gain greater access to legislators c. these groups have often been in existence for decades, allowing them to both master the legislative system and develop close ties with legislators d. the members of these groups make up the majority of voters in many districts

Which of these constitutional amendments made all people born or naturalized in the united states into citizens of the united states ?