Question: Which South Korean reality-variety show that airs on KBS2 was moved in 2013 from Wednesday nights and replaced by Star Family Show Mamma Mia?
Context: Barefooted Friends (Korean: 맨발의 친구들 ) was a South Korean reality-variety show; a part of SBS's "Good Sunday" lineup, along with "Running Man".  It was first aired on April 21, 2013.  The show is an "real outdoor hardship variety"; a spin on typical outdoor variety shows.  The members experience "real happiness" with others through challenges.  The words, "Barefooted" is supposed to mean essence, sincerity, and real hardships, where as "Friends" not only represents the cast, but the people that are met as well.  It has garnered attention as being the come-back program for Kang Ho-dong, the main MC of the program, after leaving "Good Sunday"'s "X-man" in April 2007.  After a seven-month run, the program was cancelled due to low ratings and to make room for "K-pop Star 3", with the final episode airing on November 17, 2013. Good Sunday (Korean: 일요일이 좋다 ) is a South Korean reality-variety show shown on the SBS network, which competes directly against MBC's "Sunday Night" and KBS2's "Happy Sunday" line-up.  The program has suffered from the competition of "Happy Sunday" and "Sunday Night" but reached its way to #1 on the Top 20 Charts every Sunday.  "Good Sunday" consists of a line-up of "corner programs", or segments, which air within the program.  The program ended on March 19, 2017, opting for individual programs divided into two parts for inserting commercials (which is not allowed for programs on terrestrial television). The Return of Superman (; also known as Superman Is Back) is a South Korean reality-variety show that airs on KBS2.  "The Return of Superman" is one of the two segments (the other segment is "1 Night 2 Days") on "Happy Sunday".  The original 3 episodes pilot aired as a Chuseok holiday special from September 19 till September 21 of 2013, starring Lee Hwi-jae, Choo Sung-hoon, Jang Hyun-sung, The show is narrated by actress Yoo Ho-jeong and also includes entertainer Lee Hyun-woo and his two sons. Saturday Freedom (Korean: 자유선언 토요일 ; literally "Declaration of Freedom Saturday") was a South Korean reality-variety show shown on the KBS2 network, which competes directly against MBC's "We Got Married" and "Infinite Challenge", and SBS' "Star Junior Show Bungeoppang" and "Star King".  The lineup ended on March 31, 2012, with "Immortal Songs 2" becoming a separate program and "Invincible Youth 2" moving into the time slot. Brave Family (), is a South Korean reality-variety show that airs on KBS2 beginning 23 January 2015 and estimated to air a total of 10 episode. Mamma Mia!  (promoted as Benny Andersson & Björn Ulvaeus' Mamma Mia!  and Mamma Mia!  The Smash Hit Musical) is a jukebox musical written by British playwright Catherine Johnson, based on the songs of ABBA, composed by Benny Andersson and Björn Ulvaeus, former members of the band.  The title of the musical is taken from the group's 1975 chart-topper "Mamma Mia".  Ulvaeus and Andersson, who composed the original music for ABBA, were involved in the development of the show from the beginning.  Singer Anni-Frid Lyngstad has been involved financially in the production and she has also been present at many of the premieres around the world. 2 Days & 1 Night (; also known as 1 Night 2 Days; abbreviated as 1N2D) is a South Korean reality-variety show that airs on KBS2 beginning August 5, 2007.  "1 Night 2 Days" is one of the two segments (the other segment is "The Return of Superman") on "Happy Sunday", airing at 6:25pm KST once a week.  The episodes are also uploaded with English subtitles weekly on YouTube through KBS's official channel.  The show's current cast members are Kim Jong-min, Cha Tae-hyun, Kim Joon-ho, Defconn, Yoon Shi-yoon, and Jung Joon-young.  The show's motto is "Real Wild Road Variety."  Its main concept is to recommend various places of interest that viewers can visit in South Korea.  Filming for every new trip is usually done 2 weeks prior to broadcast on KBS2. The following is a list of episodes of the South Korean reality-variety show "Let's Go!  Dream Team Season 2", broadcast on KBS2 every Sunday. Happy Sunday (Korean: 해피 선데이 ) is a Korean reality-variety show shown on the KBS2 network, which competes directly against MBC's "Sunday Night" and SBS's "Good Sunday" line-up.  Although it has been broadcast since 2003, its line-up of shows has frequently changed, with a complete revamp occurring in Spring of 2007.  At that time, three new shows were introduced – "Are You Ready", "High-Five", and "Immortal Songs".  Due to its poor reception, "Are You Ready" quickly evolved into "1 Night 2 Days", with most of its cast intact.  In late November 2008, "Happy Sunday" had a revamp of its shows keeping "1 Night 2 Days" as the second segment and bringing back "Immortal Songs" which was previously liked by viewers.  However in late March, "Immortal Songs" ended once again and was replaced with "Qualifications of Men", making "Happy Sunday" an all-male cast, with a total of 14 members.  In 2013, "Qualifications of Men" was cancelled and replaced with "Star Family Show Mamma Mia".  On November 3, 2013 "Star Family Show Mamma Mia" was moved to Wednesday nights and replaced with "The Return of Superman". The following is a list of episodes of the South Korean reality-variety show "2 Days & 1 Night", a segment of "Happy Sunday", broadcast on the KBS2 every Sunday at 4:50pm KST.  The show began airing in HD on May 23, 2010.  Episodes are aired with English subtitles not only in episode reruns, but also episodes uploaded on KBS's official YouTube channel.
Answer: The Return of Superman