What American animated sitcom had it's twenty-first season air on Comedy Central?
Put It Down (South Park): "Put It Down" is the second episode in the twenty-first season of the American animated television series "South Park". Put It Down (South Park):  The 279th episode of the series overall, it first aired on Comedy Central in the United States on September 20, 2017. South Park (season 21): The twenty-first season of the American animated sitcom "South Park" premiered on Comedy Central on September 13, 2017, and will contain ten episodes.
South Park