Question: The performer of Folk Singer is associated with which subgenre of the blues?

full_context: Document 1: Fathers and Sons (album): Fathers and Sons is the seventh studio album by American blues musician Muddy Waters, originally released as a double LP by Chess Records in August 1969.
Document 2: Rollin' Stone: The Golden Anniversary Collection: Rollin' Stone: The Golden Anniversary Collection is a compilation album collecting the first 50 master recordings of blues singer Muddy Waters for Chess Records. The collection spans Muddy's debut with then named Aristocrat Records circa 1947, and traces his evolution as a songwriter and musician up to September 17, 1952 on what became Chess Records after the company changed ownership. It is the first in a series of releases chronicling Muddy Waters' complete recording career at Chess. The second release in the series is "" (2004) and the third release in the series is "" (2012).
Document 3: Folksong '59: Upon his return to New York in 1959 after a nearly a decade spent based in London, UK, Alan Lomax produced a concert, Folksong '59, in New York City's Carnegie Hall, featuring Arkansas singer Jimmy Driftwood; the Selah Jubilee Singers and Drexel Singers (gospel groups); Muddy Waters and Memphis Slim (blues); Earl Taylor and the Stoney Mountain Boys (bluegrass); Pete Seeger, Mike Seeger (urban folk revival); and The Cadillacs (a rock and roll group).
Document 4: Chicago blues: The Chicago blues is a form of blues music indigenous to Chicago, Illinois. Chicago blues is an electric blues style of urban blues. Urban blues evolved from classic blues following the Great Migration, or the Great Northern Drive, which was both forced and voluntary at times, of African Americans from the southern United States to the industrial cities of the north, such as Chicago. Muddy Waters directly joined that migration, like many others, such as in Florida, avoiding the more harshly southern Jim Crow laws. Bruce Iglauer, founder of Alligator Records stated that, ``Chicago blues is the music of the industrial city, and has an industrial sense about it. ''Additionally, recognizing the shift in blues, Chicago blues singer and guitarist Kevin Moore expressed the blues transition stating,`` You have to put some new life into it, new blood, new perspectives. You ca n't keep talking about mules, workin 'on the levee.'' Chicago blues was heavily influenced by Mississippi bluesmen who traveled to Chicago in the early 1940s. The development of blues, up to Chicago blues, is arguably as follows: Country blues, to city blues, to urban blues. Chicago blues is based on the sound of the electric guitar and the harmonica, with the harmonica played through a PA system or guitar amplifier.
Document 5: The Real Folk Blues (Muddy Waters album): The Real Folk Blues is a 1966 compilation album of Muddy Waters recordings, released on the Chess record label in January 1966. The album was the first release of "The Real Folk Blues" series and has since been re-released on multiple formats. The album features some of Waters' first recordings.
Document 6: Muddy Waters: McKinley Morganfield (April 4, 1913 -- April 30, 1983), known professionally as Muddy Waters, was an American blues musician who is often cited as the ``father of modern Chicago blues ''.
Document 7: Folk Singer (album): Folk Singer is the fourth studio album by Muddy Waters, released in April 1964 by Chess Records. The album features Waters on acoustic guitar, backed by Willie Dixon on string bass, Clifton James on drums, and Buddy Guy on acoustic guitar. It is Waters's only all-acoustic album. Numerous reissues of "Folk Singer" include bonus tracks from two subsequent sessions, in April 1964 and October 1964.
Document 8: W. C. Handy: William Christopher Handy (November 16, 1873 -- March 28, 1958) was a composer and musician, known as the Father of the Blues. An African American, Handy was one of the most influential songwriters in the United States. One of many musicians who played the distinctively American blues music, Handy did not create the blues genre and was not the first to publish music in the blues form, but he took the blues from a regional music style (Delta blues) with a limited audience to a new level of popularity.
Document 9: Big Bill Morganfield: William "Big Bill" Morganfield (born June 19, 1956) is an American blues singer and guitarist, who is the son of Muddy Waters.
Document 10: King Bee (album): King Bee is the fourteenth and final studio album by blues singer and guitarist Muddy Waters. Released in 1981, it is third in a series of records done for the label Blue Sky Records under producer/guitarist Johnny Winter. Recorded in three days (and in the wake of Muddy's failing health) some of the band members, namely Winter and guitarist Bob Margolin, were not happy with the result. As his health deteriorated, Muddy was forced to cancel an increasing number of shows. He died of a heart attack on April 30, 1983.
Document 11: Howlin' Wolf: Chester Arthur Burnett (June 10, 1910 – January 10, 1976), known as Howlin' Wolf, was a Chicago blues singer, guitarist, and harmonica player, originally from Mississippi. With a booming voice and imposing physical presence, he is one of the best-known Chicago blues artists. The musician and critic Cub Koda noted, "no one could match Howlin' Wolf for the singular ability to rock the house down to the foundation while simultaneously scaring its patrons out of its wits." Producer Sam Phillips recalled, "When I heard Howlin' Wolf, I said, 'This is for me. This is where the soul of man never dies. Several of his songs, including "Smokestack Lightnin'", "Killing Floor" and "Spoonful", have become blues and blues rock standards. In 2011, "Rolling Stone" magazine ranked him number 54 on its list of the "100 Greatest Artists of All Time".
Document 12: After the Rain (Muddy Waters album): After the Rain is the sixth studio album by Muddy Waters, a follow-up to the previous years' "Electric Mud" and sharing many of the musicians from that album. Unlike "Electric Mud", "After the Rain" contained mostly his own compositions and the songs, while still distorted, are less overtly psychedelic.
Document 13: Diddy Wah Diddy: "Diddy Wah Diddy" was Bo Diddley's fourth single release on Checker Records, and was released in early 1956. The song was recorded on November 10, 1955 in Chicago, Illinois. The recording featured The Moonglows on backing vocals, Willie Dixon on bass, Jody Williams along with Bo Diddley on guitar, Clifton James on drums, Jerome Green playing the maracas, and Little Willie Smith on harmonica.
Document 14: Forty Days and Forty Nights: "Forty Days and Forty Nights" is a blues song recorded by Muddy Waters in 1956. Called "a big, bold record", it was a hit, spending six weeks in the "Billboard" R&B chart, where it reached number seven. "Forty Days and Forty Nights" has been interpreted and recorded by a variety of artists.
Document 15: Hard Again: Hard Again is the twelfth studio album by American blues singer Muddy Waters. It was recorded by produced by Johnny Winter.
ground_truth: Chicago blues
sub_queries: Folk Singer >> performer Answer: Muddy Waters
Muddy Waters is associated with which subgenre of the blues Answer: Chicago blues