Question: Which singer, Lee Gi-kwang or Kenny Greene, originally debuted as solo singer with the stage name AJ?

Context paragraphs:
Dana (South Korean singer): Hong Sung-mi (Hangul: 홍성미, Hanja: 洪性美, born 17 July 1986), commonly known by her stage name Dana, is a South Korean singer, musical actress and vocal coach.  Although she was originally a solo singer, which debuting in 2001 and later debuted as a member of South Korean girl group The Grace in 2005.

Raina (singer): Oh Hye-rin (born May 7, 1989), better known by her stage name Raina, is a South Korean singer-songwriter.  She is the main vocalist of South Korean girl group After School and also the leader of After School sub-unit Orange Caramel.  Raina debuted with the group in November 2009 following the release of the group's second single, "Because of You".  She debuted as a solo singer in September 2014 with the single "You End, And Me".

AJ Nelson: Agyei Nelson Yaw (born 5 May 1985), better known by his stage name AJ Nelson is a Ghanaian recording artist.  He is most famous for the singles “Same Girl”, “Faith” and “Power to the People” and is currently the only rapper who fuses the Bono language with Ashanti Twi in his songs.  In 2015, AJ Nelson initiated a campaign titled “Power To the People” to empower the youth of his homeland, Ghana and of the African continent to speak against woes of society since he felt there was much corruption and conflicts on the African continent but the people mostly affected could hardly voice their thoughts and emotions to the leaders of society.  The campaign attracted the attention of important figures like Communication Director at World Bank, Mr. Kofi Tsikata k and Bella Mundi of GH One TV who joined the campaign.  In the same period, AJ Nelson released a hiphop song titled “Power to the People”.  In November 2015, the song was ranked the 3rd most downloaded Ghanaian Hiphop Song on iTunes.  AJ Nelson was ranked the 3rd top selling artist on iTunes in November 2015.

Intro (R&amp;B group): Intro is an American R&B trio from Brooklyn, New York City, New York.  The trio consisted of members Jeff Sanders, Clinton "Buddy" Wike and lead singer/songwriter Kenny Greene.  Intro released two albums (for Atlantic Records): 1993's "Intro" and their second album, 1995's "New Life".  The group had a string of US hits in the 1990s.  The hits included the singles "Let Me Be The One", the Stevie Wonder cover "Ribbon in the Sky", "Funny How Time Flies" and their highest charting hit, "Come Inside".  Greene died from complications of AIDS in 2001, which led to the group's disbanding.

Lizzy (singer): Park Soo-young (born July 31, 1992), better known by her stage name Lizzy, is a South Korean singer and actress.  She is a member of the girl group After School and its sub-unit Orange Caramel.  In March 2010, she debuted in After School with the release of their third single, "Bang! ", and debuted as a solo singer in January 2015 with "Not an Easy Girl".  She has acted in various films and television shows, including "All My Love" (2011), "Love Forecast" (2015) and "Angry Mom" (2015).

Highlight (band): Highlight (Korean: 하이라이트 ) is a South Korean boy band formerly known as Beast (Korean: 비스트).  The band consists of five members: Yoon Doo-joon, Yong Jun-hyung, Yang Yo-seob, Lee Gi-kwang, and Son Dong-woon.  Original member Jang Hyun-seung officially left the group in April 2016.  Later that year, the five remaining members moved labels from Cube Entertainment to Around Us Entertainment and subsequently changed their name to Highlight in 2017.

Miz: Mizuki Watanabe (渡邊瑞枝 , Watanabe Mizuki , born March 6, 1981 in Kitami, Hokkaidō, Japan) , better known simply as Miz, is a Japanese pop/rock singer and actress.  Though most of her music is released in Japan, she does her work primarily from Gotland in Sweden, mainly doing promotional videos, photo shoots and recording there.  She originally debuted in 1999 under Universal Music Japan using her real name, Watanabe Mizuki, releasing two singles.  In 2003, she began working with the Swedish producer Tord Backstrom and debuted under Victor Entertainment with the pseudonym Miz in 2004.  That same year, she released an English album in Sweden, with the lead single "Waiting" reaching #8 on the Hitlistan Swedish singles chart.  In 2007, Watanabe returned to Universal Music Japan, changed her stage name to Mizrock, and released her first mini-album "Good bye, yesterday" and three singles.  However, in 2009 she announced on her official blog that she had changed her stage name back to Miz.  Her biggest hits in Japan are "New Day" and "In The Sky", the theme song for the Square Enix role-playing video game "Grandia III".

Lee Gi-kwang: Lee Gi-kwang (Korean: 이기광 ; born March 30, 1990), known professionally as Gikwang or Kikwang, is a South Korean singer-songwriter and actor.  He originally debuted as solo singer with the stage name AJ (Ace Junior), releasing his first mini album "First Episode: A New Hero" on April 4, 2009.  In October 2009, he debuted as the main dancer, visual and a lead vocalist of boy group BEAST which had been renamed to Highlight in February 2017.

Lee Jung: Lee Jung-hee (이정희 , born October 24, 1981), better known by his stage name Lee Jung or J. Lee, is a South Korean singer and actor.  He made his debut as a member of 7 Dayz; Lee has since become a solo singer.  Although his last album has underperformed, he has continued his popularity by becoming a mainstay on KBS's "Heroine 6", becoming part of the "Gag Team 3" with Shin Jung Hwan from Country Kko Kko and Kim Jong Min from Koyote.

Kenny Greene: Kenny Greene (January 17, 1969 – October 1, 2001) was an American singer-songwriter who was also a member of the R&B group Intro.

Supporting paragraphs: Lee Gi-kwang Kenny Greene
Answer: Lee Gi-kwang