Slim Moon (b. Matthew Moon on October 15, 1967) is the founder of the independent music label, Kill Rock Stars.
 He also started its sister label, 5 Rue Christine.
 Slim ran KRS from 1991 to 2006, during which time KRS released albums by dozens of artists including Sleater-Kinney, Elliott Smith, The Decemberists, Miranda July, Bikini Kill, Unwound, Huggy Bear, The Gossip, and Linda Perry.
 Slim and his wife, who now runs KRS, decided to make 5RC dormant, and in 2007 5RC released its final records for the present time.
William Francis "Billy" Karren is an American musician, best known as the lead guitarist of the punk/riot grrrl band Bikini Kill, formed by Kathleen Hanna, with Karren, Tobi Vail and Kathi Wilcox.
 He was also active in many other music projects including the Go Team, the Frumpies, Corrections, and Spray Painted Love (with Tobi Vail).
Bikini Kill is the first EP by the American punk rock band Bikini Kill led by singer Kathleen Hanna.
 The six-song vinyl EP was released in 1992 on Kill Rock Stars.
 It was produced by Fugazi's Ian MacKaye.
 In 1994, the EP was released on CD together with the "Yeah Yeah Yeah Yeah" EP under the name "The CD Version of the First Two Records".
The Singles is a compilation album of three singles by punk rock band Bikini Kill.
 The album was released in 1998 by Kill Rock Stars.
 Joan Jett produces, plays guitar and sings on the first three tracks.
Our Troubled Youth is the Huggy Bear side of a split album they released with Bikini Kill (whose side was entitled "Yeah, Yeah, Yeah, Yeah").
 It was released on International Women's Day 1993 on Catcall Records in the United Kingdom, and on the Kill Rock Stars label in the United States.
Bikini Kill was an American punk rock band formed in Olympia, Washington, in October 1990.
 The group consisted of singer and songwriter Kathleen Hanna, guitarist Billy Karren, bassist Kathi Wilcox, and drummer Tobi Vail.
 The band is widely considered to be the pioneer of the riot grrrl movement, and was known for its radical feminist lyrics and fiery performances.
 Their music is characteristically abrasive and hardcore-influenced.
 After two full-length albums, several EPs and two compilations, they disbanded in 1997.
Yeah Yeah Yeah Yeah is the Bikini Kill side of a split album between American and English riot grrrl bands Bikini Kill and Huggy Bear.
 It was released in 1993 on Kill Rock Stars.
 The Huggy Bear side was entitled "Our Troubled Youth".
 Bikini Kill reissued their side on their imprint Bikini Kill Records on April 15, 2014.
 They did not have the rights to the Huggy Bear side, and instead paired it with unreleased live tracks.
Reject All American is the final studio album by the American punk rock band Bikini Kill, released on April 5, 1996 by Kill Rock Stars.
 The album received generally favorable reviews from music critics.
Pussy Whipped is the debut studio album by American punk rock band Bikini Kill.
 It was released on Kill Rock Stars on October 26, 1996.
 It includes the track "Rebel Girl", which is number 27 on the "Rolling Stone" list of "Most Excellent Songs of Every Year Since 1967", a playlist assembled by the magazine in 2006 to celebrate its 1,000th issue.
The Three O'Clock is an American alternative rock group associated with the Los Angeles 1980s Paisley Underground scene.
 Lead singer and bassist Michael Quercio is credited with coining the term "Paisley Underground" to describe a subset of the 1980s L.A. music scene which included bands such as Dream Syndicate, Rain Parade, Green on Red, and the Bangles.

Question: Which rock group, either Bikini Kill or The Three O'Clock, was active in the earlier years in the US?
Answer: The Three O'Clock