Dreamgirls musical supervisors Randy Spendlove and Matt Sullivan hired R&B production team The Underdogs -- Harvey Mason, Jr. and Damon Thomas -- to restructure and rearrange the Henry Krieger/Tom Eyen Dreamgirls score so that it better reflected its proper time period, yet also reflected then-modern R&B/pop sensibilities. During post-production, composer Stephen Trask was contracted to provide additional score material for the film. Several musical numbers from the Broadway score were not included in the film version, in particular Lorrell's solo "Ain't No Party".  Four new songs were added for the film: "Love You I Do", "Patience", "Perfect World," and "Listen."  All of the new songs feature music composed by original Dreamgirls stage composer Henry Krieger. With Tom Eyen having died in 1991, various lyricists were brought in by Krieger to co-author the new songs. "Love You I Do," with lyrics by Siedah Garrett, is performed in the film by Effie during a rehearsal at the Rainbow Records studio. Willie Reale wrote the lyrics for "Patience," a song performed in the film by Jimmy, Lorrell, C.C., and a gospel choir, as the characters attempt to record a message song for Jimmy. "Perfect World," also featuring lyrics by Garrett, is performed during the Rainbow 10th anniversary special sequence by Jackson 5 doppelgangers The Campbell Connection. "Listen", with additional music by Scott Cutler and Beyonce Knowles, and lyrics by Anne Preven, is presented as a defining moment for Deena's character late in the film.  After preview screenings during the summer of 2006, several minutes worth of musical footage were deleted from the film due to negative audience reactions to the amount of music. Among this footage was one whole musical number, C.C. and Effie's sung reunion "Effie, Sing My Song", which was replaced with an alternative spoken version.  The Dreamgirls: Music from the Motion Picture soundtrack album was released on December 5 by Music World Entertainment/Columbia Records, in both a single-disc version containing highlights and a double-disc "Deluxe Version" containing all of the film's songs. The single-disc version of the soundtrack peaked at number-one on the Billboard 200 during a slow sales week in early January 2007. "Listen" was the first official single from the soundtrack, supported by a music video featuring Beyonce. "And I Am Telling You I'm Not Going" was the Dreamgirls soundtrack's second single. Though a music video with all-original footage was once planned, the video eventually released for "And I Am Telling You" comprised the entire corresponding scene in the actual film.

Answer this question "Why were they deleted?" by extracting the answer from the text above.
due to negative audience reactions to the amount of music.