The show will feature the popular group Pentatonix performing holiday favorites, as well as performances by special guests Reba McEntire and Kelly Clarkson. The show can be seen on WKYC-TV Channel 3 and WTOV-TV Channel 9. If you. "America’s Got Talent" winner Darci Lynne Farmer, the talented 13-year-old singing ventriloquist from Oklahoma City, will be among the special guests on "A Very Pentatonix Christmas," airing at 9 tonight on NBC….