Which popular twentieth century musical style was developed in the usa with roots in blues and ragtime

The popular 20th century musical style that was developed in the United States with roots in blues and ragtime is jazz.

Explanation:

Jazz is a musical genre born in the early 20th century in the United States.

The musical identity of 'jazz' is complex and can not be easily delimited, although its most definited influence can be seen in blues and ragtime.

Although jazz is a product of African-American culture, it has always been open to influences from other musical traditions, and since the 1920s it has been performed by musicians from different parts of the world with a very different background.

c or d both can be the answer