Question: Which character in the adult animated film, created by Trey Parker and Matt Stone, is known for his muffled and indiscernible speech?

Context paragraphs:
List of South Park cast members: "South Park" is an American adult animated sitcom created by Trey Parker and Matt Stone who also do the majority of the voices.  Both Parker and Stone do most of the male characters on the show along with April Stewart and Mona Marshall, who do the female characters on the show.  Guest stars have lend their voices to the show including Jay Leno, George Clooney, Robert Smith and the comedy duo Cheech & Chong voiced characters representing their likenesses for the season four (2000) episode "Cherokee Hair Tampons", which was the duo's first collaborative effort in 20 years.

South Park: Bigger, Longer &amp; Uncut: South Park: Bigger, Longer & Uncut is a 1999 American adult animated musical comedy film based on the Comedy Central animated television series "South Park".  The film was directed by series creator Trey Parker and stars the regular television cast of Parker, Matt Stone, Mary Kay Bergman, and Isaac Hayes, with guest performances by George Clooney, Eric Idle and Mike Judge.  The film follows the four boys Stan Marsh, Kyle Broflovski, Eric Cartman, and Kenny McCormick as they sneak into an R-rated film featuring Canadian actors Terrance and Phillip and begin cursing incessantly.  Eventually, their mothers pressure the United States to wage war against Canada for allegedly corrupting their children.

Kenny McCormick: Kenneth "Kenny" McCormick is a main character in the animated adult television series "South Park", along with his friends Stan Marsh, Kyle Broflovski, and Eric Cartman.  His oft-muffled and indiscernible speech—the result of his parka hood covering his mouth—is provided by co-creator Matt Stone.  He debuted on television when "South Park" first aired on August 13, 1997, after having first appeared in "The Spirit of Christmas" shorts created by Stone and long-time collaborator Trey Parker in 1992 ("Jesus vs. Frosty") and 1995 ("Jesus vs. Santa").

South Park (season 7): Season seven of "South Park", an American animated television series created by Trey Parker and Matt Stone, began airing on March 19, 2003.  The seventh season concluded after 15 episodes on December 17, 2003, and was written and directed by Trey Parker.

South Park (season 8): Season eight of "South Park", an American animated television series created by Trey Parker and Matt Stone, began airing on March 17, 2004.  The eighth season concluded after 14 episodes on December 15, 2004, and was written and directed by Trey Parker.  The season deals with various topics that were relevant at the time of release.  The episodes portray a spectrum of topics, from effect of large scale retails corporations to immigration.

Eric Cartman: Eric Theodore Cartman, often referred to as just Cartman, is a main character in the animated television series "South Park", created by Matt Stone and Trey Parker, and voiced by Trey Parker.  Cartman, generally referred to by his surname, is one of four central characters in "South Park", along with his friends Stan Marsh, Kyle Broflovski, and Kenny McCormick.  Cartman first appeared, originally named Kenny, in prototypical form in a 1992 animated short "Jesus vs. Frosty", and a 1995 animated short "Jesus vs. Santa", and first appeared on television in the pilot episode of "South Park", "Cartman Gets an Anal Probe", on August 13, 1997.

South Park (season 2): Season two of "South Park", an American animated television series created by Trey Parker and Matt Stone, began airing on April 1, 1998.  The second season concluded after 18 episodes on January 20, 1999; it remains the longest season of "South Park" to date.  While most of the episodes were directed by series creator Trey Parker, Season 2 includes two episodes directed by Eric Stough.

South Park (season 9): Season nine of "South Park", an American animated television series created by Trey Parker and Matt Stone, began airing on March 9, 2005.  The ninth season concluded after 14 episodes on December 7, 2005.  All of the episodes in the ninth season were written and directed by Trey Parker.

South Park: South Park is an American adult animated sitcom created by Trey Parker and Matt Stone and developed by Brian Graden for the Comedy Central television network.  The show revolves around four boys—Stan Marsh, Kyle Broflovski, Eric Cartman, and Kenny McCormick—and their bizarre adventures in and around the titular Colorado town.  Much like "The Simpsons", "South Park" uses a very large ensemble cast of recurring characters and became infamous for its profanity and dark, surreal humor that satirizes a wide range of topics towards a mature audience.

South Park (season 10): The tenth season of "South Park", an American animated television series created by Trey Parker and Matt Stone, began airing on March 22, 2006.  The tenth season concluded after 14 episodes on November 15, 2006.  This is the first season in which Kenny does not die and the last season featuring Isaac Hayes (the voice of Chef) as Hayes quit the show following the backlash behind season nine's "Trapped in the Closet" episode.  This season also had a minor controversy when the Halloween episode "Hell on Earth 2006" depicted "The Crocodile Hunter's" Steve Irwin with a stingray lodged in his chest getting thrown out of Satan's Halloween party for not being in costume.  Episode 2 in this season is the last one with the Braniff Airlines logo.  All the episodes in this season were written and directed by Trey Parker.

Supporting paragraphs: Kenny McCormick South Park
Answer: Kenneth "Kenny" McCormick