Final answer:
Rock and roll music emerged in the 1950s and relied heavily on Black musical traditions. White musicians like Elvis Presley followed the lead of African Americans in creating this new genre.
Step-by-step explanation:
The emergence of rock and roll music as a part of 1950's popular culture in the United States relied heavily on Black musical traditions. It had its roots in West African call-and-response traditions and the pioneers of this new rhythm and blues sound were African Americans. White musicians like Elvis Presley followed their lead and enjoyed both instant celebrity as well as controversy.