Boston-based interior designer Taniya Nayak is returning as co-host of “The Great Christmas Light Fight’’ on ABC. This marks the fourth season of the reality TV competition, which features families from across the country “decorating their homes to the extreme’’ as they compete for cash prizes and the “Light Fight’’ trophy. The series will air Monday nights for three consecutive weeks with back-to-back episodes on Dec. 5, 12, and 19. Pictured are Nayak and co-host CARTER OOSTERHOUSE.