Question: Kiley Dean was a back-up singer for what famous singer, who was also known as the Queen of Pop?
Context: "Who Will I Run To?"  is the second single from Pop/R&B singer Kiley Dean's unreleased album "Simple Girl" during the third quarter of 2003. Joan Hecht is an American humanitarian and award winning author of the book "The Journey of the Lost Boys".  She is also the founder and President of the 501 c-3 non-profit Alliance for the Lost Boys of Sudan, an organization that assists with the health and educational needs of Lost Boys and their families living in the United States and Africa.  Hecht formerly traveled as a back-up singer for The Johnny Van Zant Band and began recording professionally at age 14.  However, she is best known for her work related to the Lost Boys of Sudan, including engaging in public speaking on their behalf and that of the people of South Sudan, as well as writing an award winning book about them titled, "The Journey of the Lost Boys". Madonna Louise Ciccone ( ; born August 16, 1958) is an American singer, songwriter, actress, and businesswoman.  A leading presence during the emergence of MTV in the 1980s, Madonna is known for pushing the boundaries of lyrical content in mainstream popular music, as well as visual imagery in music videos and on stage.  She has also frequently reinvented both her music and image while maintaining autonomy within the recording industry.  Besides sparking controversy, her works have been acclaimed by music critics.  Referred to as the "Queen of Pop", Madonna is widely cited as an influence by other artists. Kiley Dean (born April 12, 1982) is an American contemporary R&B singer.  Dean was born and raised in a small town in Arkansas.  When she was about 7 years old, her family decided to move to Orlando.  She grew up singing in school and church, which led her to singing back-up for Britney Spears' tours, "…Baby One More Time Tour" and "Oops! ... I Did It Again World Tour" as well as Madonna's tours, "MDNA Tour" and "Rebel Heart Tour." Arnold McCuller is an American vocalist, songwriter, and record producer, born and raised in Cleveland, Ohio.  He is active as a solo artist and session musician, but is perhaps best known for his work as a touring back-up singer with artists such as James Taylor, Phil Collins, Beck, Bonnie Raitt, and Todd Rundgren.  He has toured for thirty years with Taylor and is an audience favorite for his featured vocal parts on the songs "Shower the People", "I Will Follow", and "Is That the Way You Look".  He has also toured extensively with Collins and is one of the main lead vocalists on the live version of "Easy Lover".  In 2010 McCuller joined the Troubadour Reunion Tour supporting James Taylor and Carole King. Week End Tour was the name given to French pop singer Lorie's second concert tour, inspired by her hit single "Week End".  On 4 October 2004, a live recording of the show was released in two versions, as with the famous singer's previous live effort, "Live Tour": a regular jewel case release containing the CD and a DVD and a limited edition cardboard box also containing a poster and a watch featuring the blonde songstress during her performances. On 12 June 2004, a filmed version of the show was released on DVD, once again in two versions.  The limited edition DVD additionally contained a bonus disc with additional special features, as well has a new, double-sided poster and a removable tattoo of the singer's name. "Make Me a Song" is the debut single by Pop/R&B singer Kiley Dean, released in May 2003.  It peaked at #59 on the "Billboard" Hot 100. Catherine Porter is an American singer, songwriter, and musician.  She is a former member of The Brian May Band and has appeared in several musicals and films.  To date, Porter has released one album of solo material, "Something Good", in 2002, and has also worked as a back-up singer for Queen, Tony Hadley, Edwin Starr, Kiki Dee, Paul Rodgers, Sam Moore, Mel B and Chaka Khan. Seela Misra is a Canadian-born singer/songwriter residing in Austin, Texas.  She was the lead singer of the jazz band TOrcH and is also the back-up singer for Matt The Electrician.  Seela is known for an expressive vocal range, “one moment she rasps like a Jersey deli queen, the next she's cooing coquettishly.”  This is evident in her solo work and when delivering jazz standards with the Jazz Pharaohs or with TOrcH where she has been credited with “unswerving hipness” succeeding where others have failed “in melding her own style with those from the past.” Music '89 was the first ever all pop music stage-show to be aired on Pakistan TV.  It was aired in January 1989, on PTV (Pakistan state run TV channel).  The show was directed by Shoaib Mansoor and hosted by the famous singer Nazia Hassan and her brother, Zohaib Hassan.  It was a revolutionary show that introduced a new breed of young musicians post Nazia and Zoheb.  The show was the launching pad for many new talents including Vital Signs, Ali Haider, Sajjad Ali, Jupiters, Strings, while also introducing underground, "alternative" bands including Final Cut and The Barbarians
Answer: Madonna