Article: The thirteenth season premiered on January 15, 2014, with Ryan Seacrest returning as host. Randy Jackson and Keith Urban returned, though Jackson moved from the judging panel to the role of in-mentor. Mariah Carey and Nicki Minaj left the panel after one season. Former judge Jennifer Lopez and former mentor Harry Connick, Jr. joined Urban on the panel. Also, Nigel Lythgoe and Ken Warwick were replaced as executive producers by Per Blankens, Jesse Ignjatovic and Evan Pragger. Bill DeRonde replaced Warwick as a director of the audition episodes, while Louis J. Horvitz replaced Gregg Gelfand as a director of the show.

Question: Which former judge came back to the judges' panel this season?
Jennifer Lopez