Answer by taking a quote from the following article:

C+C Music Factory is an American musical group formed in 1989 by David Cole and Robert Clivilles. The group is best known for their five hit singles: "Gonna Make You Sweat (Everybody Dance Now)",

In 1989 Clivilles and Cole hired the artists Zelma Davis (Vocalist), Martha Wash (Vocalist) and Freedom Williams (MC) to vocalize all the tracks for Gonna Make You Sweat, the group's first album. In 1990 it peaked at No. 2 on the Billboard 200 album chart, No. 11 on the R&B album chart, and went 5x platinum. Elana Cooper was hired as Lead Vocalist for the initial overseas tour(s) awaiting Zelma Davis green card clearance.  All four singles from their debut album reached No. 1 on the Billboard Dance/Club Play chart, and all four were also crossover Pop and R&B hits. The first single, "Gonna Make You Sweat (Everybody Dance Now)", reached No. 1 on the Billboard Hot 100 and R&B Singles chart (and No. 3 in the UK). The fourth and final single from their debut album, "Just a Touch of Love", featured in the movie Sister Act. The album contained two more Top 5 singles; "Here We Go (Let's Rock & Roll)" reached No. 3 on Billboard's Hot 100 chart (and No. 20 in the UK), and "Things That Make You Go Hmmm" (inspired by a phrase uttered periodically by late-night talk show host, Arsenio Hall) reached No. 4 (and No. 4 in the UK).  In 1992, they had another No. 1 Dance/Club play hit with the song "Keep It Comin'" (Dance Till You Can't Dance No More); with emcee Q-Unique and lead and background vocalist Deborah Cooper that was recorded for the soundtrack and opening cheerleading routine from the movie Buffy the Vampire Slayer.

Was their music on any other movies?
the soundtrack and opening cheerleading routine from the movie Buffy the Vampire Slayer.