Final answer:
Chick Corea became prominent in the 1960s and formed the fusion group Return to Forever in 1970.
Step-by-step explanation:
The influential jazz pianist Chick Corea became prominent in the 1960s, forming, in 1970, a popular and influential fusion group, Return to Forever. Therefore, the correct answer is b)1960s. Chick Corea was an integral part of the jazz scene, which has its roots in the early 20th century, evolving from ragtime and blues. In the 1920s, Harlem Renaissance was a significant period for jazz, with iconic musicians like Duke Ellington and Cab Calloway performing in nightclubs such as the Cotton Club.
Later decades saw new styles and periods, including the 'cool' culture of jazz in the 1940s. Chick Corea's work in the 1960s and 1970s played a crucial role in the development of jazz fusion, a genre that blends jazz with other styles like rock, funk, and Latin music.