Question: When were the group, that provided vocals for 1974 hit TSOP, originally formed ?

<P0-S0> Masta Ace Incorporated was a Hip Hop crew formed by rapper Masta Ace. <P0-S1>  The group, also known as "The I.N.C.", included Eyceurokk (Eyce, Uneek and Rokkdiesel), Lord Digga, Paula Perry and R&B vocalist Leschea. <P0-S2>  Ace first gained notice in the rap world as a member of the legendary Juice Crew, and with the release of his acclaimed 1990 debut "Take a Look Around", which featured an appearance from Eyceurokk. <P0-S3>  In 1992, Ace formed the I.N.C. crew and recorded their first group album, "SlaughtaHouse", which was released in May 1993. <P0-S4>  Ace provided almost all of the rapping, with Lord Digga serving as the hype-man. <P0-S5>  Digga was also responsible for a bulk of the beats, producing five of the album's songs as part of the duo Bluez Brothers. <P0-S6>  Paula Perry was the main performer on the song ""Who U Jackin'?"" <P0-S7> , Leschea provided vocals for ""Don't Fuck Around (Outro)"", and Eyceurokk appeared on the tracks '"Slaughtahouse"' (as MC Negro), ""Ain't U Da Masta"" and ""Saturday Nite Live"". <P0-S8>  The album was highly acclaimed, but sold only moderately well. <P0-S9>  Some versions of "SlaughtaHouse" included the hidden bonus track, ""Born to Roll"", which became a huge hit in 1994, breaking into the Top 25 on the "Billboard" Hot 100 singles chart. <P0-S10>  Eyceurokk split from the crew after "SlaughtaHouse", leaving the group to four members. <SEP> <P1-S0>  Although a total of 15 women have been a member over the years, the group has always been a trio. <P1-S1>  The current line-up consists of Valerie Holiday, Helen Scott and Freddie Pool. <P1-S2>  Holiday has been a member since she first joined in 1967, while Scott has been a permanent member since 1976, having previously been in the group from 1963 to 1966. <P1-S3>  The group were particularly successful in the UK, achieving 13 Top 50 hit singles between 1974 and 1985. <P1-S4> The Three Degrees are an American female vocal group, who were originally formed in 1963 in Philadelphia, Pennsylvania. <SEP> <P2-S0> Real Ones also known as Reelones, is a Folk/rock band from Bergen, Norway, which was formed in 1994 when the members were 14 and 15 years of age. <P2-S1>  Band members include Ivar Vogt (vocals, guitar, ukulele, saxophone), Jørgen Sandvik (vocals, guitar, banjo, sitar), Kåre Opheim (drums, backing vocals), Øystein Skjælaaen (bass, backing vocals), and David Vogt (vocals, violin, organ). <P2-S2>  1994-2009 Yrjan Tangenes provided vocals, percussion, and bodhrán, and Thomas Lønnheim played percussion in 1999-2000 <SEP> <P3-S0>  A classic example of the Philadelphia soul genre, it was written by Kenneth Gamble and Leon Huff as the theme for the American musical television program "Soul Train", which specialized in African American musical performers. <P3-S1> "TSOP (The Sound of Philadelphia)" is a 1974 hit recording by MFSB (Mother, Father, Sister, Brother) featuring vocals by The Three Degrees. <P3-S2>  The single was released on the Philadelphia International label. <P3-S3>  It was the first television theme song to reach number one on the "Billboard" Hot 100, and it is arguably the first disco song to reach that position.