Question: What American singer, film actor and comedian, suddenly stood up during a performance of Gershwin's Liza (All the Clouds'll Roll Away) and started singing?  
Context: Sook-ja "Sue" Kim (born 1941) is a Korean-born U.S. singer.  She started singing with her sisters in a group called The Kim Sisters at the age of 10 and played 13 different instruments.  In 1950, the Korean War broke out and Sue Kim's father, Kim Hae-song, who was a famous Korean symphony orchestra conductor was captured by the North Korean army and later assassinated.  Her mother, Lee Nan-young, was left with no home, no food and no money for her and her seven children.  Lee was a famous Korean singer who rose to stardom with the song "Mokpo Tears."  In 1953, Lee asked the children to perform with her in South Korea's military clubs to support their family.  The GIs donated rock and roll records for the sisters to memorize and sing, and in turn the sisters received chocolate bars and alcohol, which they exchanged for food.  The GIs that returned to the States spread the word about the talented trio and in 1958, Tom Ball (who later became The Kim Sisters’ manager) heard about the sisters from one of the returning GIs and went to Korea to recruit them for an Asian act that he was producing. Babu Bogati (Nepali: बाबु बोगटी ) is a pop singer and actor from Nepal.  He has also played in several television shows.  He started off his career as a singer.  He featured his first song called maya ko aauti chino.  After that he started singing and sing several songs before he started acting.  In 2010 his first flim released called bato muniko phul and he began his career as an actor. "Liza (All the Clouds'll Roll Away)" is a song composed by George Gershwin with lyrics by Ira Gershwin and Gus Kahn.  It was introduced in 1929 by Ruby Keeler (as Dixie Dugan) in Florenz Ziegfeld's musical "Show Girl".  The stage performances were accompanied by the Duke Ellington Orchestra.  On the show's opening night in Boston on June 25, 1929, Keeler's husband and popular singer Al Jolson suddenly stood up from his seat in the third row and sang a chorus of the song, much to the surprise of the audience and Gershwin himself.  Jolson recorded the song a few days later on July 6, 1929, and his rendition rose to number nine on the charts of the day. Kyle John Echarri (born June 20, 2003) is a Filipino-American singer, recording artist, and actor.  He was born in Orange County, California and started singing at the age of two.  His family moved to Cebu City, Philippines in June 2014.  Echarri rose to prominence and made his first television appearance at the age of eleven when he joined season 2 of "The Voice Kids", where he landed Top 6 under Sarah Geronimo's Team Just six seconds after he started singing One Direction's "Night Changes" during the blind auditions, Coaches Bamboo and Sarah already turned for the then 11-year-old Cebuano footballer eventually choosing to be part of Team Sarah.  A commemorative album was then released by MCA Music featuring Kyle Echarri's performances tracks "Got To Believe In Magic" and "Hero". Davy Knowles (born 30 of April 1987) is a Manx blues guitarist and singer.  Knowles currently tours as a solo artist, but is formerly of the blues-rock band Back Door Slam, as well as working under the name Davy Knowles and Back Door Slam for a short period of time.  With Back Door Slam, he played lead guitar and sang on their debut album, "Roll Away".  After a split-up with bassist Adam Jones and drummer Ross Doyle, Knowles released the first and only album under the name Davy Knowles and Back Door Slam, "Coming Up for Air", on 19 May 2009.  Knowles drew his musical influences from blues musicians that he grew up listening to such as Dire Straits, Peter Green, and Eric Clapton's Cream.  Due to his home country's proximity to Ireland, Knowles has stated that his music also is influenced by the Celtic genre, which is noted to be present in the song "Roll Away".  In April 2009, Knowles toured with British guitarist Jeff Beck on his American tour, where he was the opening act.  He toured with Joe Satriani and Chickenfoot in the United States through December 2009.  Davy Knowles toured with The Rhythm Devils in 2010. Sunanda Patnaik (born 7 November 1934) is an Indian classical singer of Gwalior gharana from Odisha.  Popularly known as "guruma", she is considered one of the great dames of Hindustani music.  She is the daughter of legendary Oriya poet Baikunthanath Patnaik.  She started singing at All India Radio in Cuttack in 1948 at the age of 14.  The then Odisha Governor Asaf Ali once heard her on Radio and was very impressed with her singing and she became a regular fixture at the Raj Bhavan whenever the Governor had guests.  Once, President Rajendra Prasad heard her at Puri.  He was very impressed with her singing and arranged her training under Pandit Vinayak Rao Pattavardhan at Pune with a scholarship.  She was awarded with the degree of Masters in Music by Pune School in 1956.  She performed at All India Sadrang Sageet Sammelan in Calcutta in September 1957 where she received 13 gold coins.Since then has done many concerts in India and is known internationally.  She is best known for her tarana that she sings at a high pace and is considered one of the best contemporary interpreters of Odissi music.  She has been staying at Kolkata since 1983. Al Jolson (born Asa Yoelson; May 26, 1886 – October 23, 1950) was an American singer, film actor, and comedian.  At the peak of his career, he was dubbed "The World's Greatest Entertainer."  His performing style was brash and extroverted, and he popularized a large number of songs that benefited from his "shamelessly sentimental, melodramatic approach."  Numerous well-known singers were influenced by his music, including Bing Crosby, David Bowie, Bob Dylan, Rod Stewart and others.  Dylan once referred to him as "somebody whose life I can feel."  Broadway critic Gilbert Seldes compared him to the Greek god Pan, claiming that Jolson represented "the concentration of our national health and gaiety." Alketa Vejsiu (Born 19 January 1984 in Tirana) is an Albanian singer, TV personality, producer and radio presenter.  She started her career as a radio presenter in Top Albania Radio, after that she started singing and hosting TV shows in many television stations in Albania.  Her singing career started in her early ages, where she participated in RTSH festivals. Aniruddha Bhattacharya is a professional playback vocalist in the Telugu film industry.  He hails from Kolkata, West Bengal.  He started singing at the age of 5 and underwent training in Indian Classical Music under several stalwarts the most recent being Pt.  Falguni Mitra of Bettiah Benaras Gharana.  He has acquired many styles of singing including the steadiness and open voiced recitals required in Dhrupad and Dhamar.  As he progressed through his teens and matured as a singer he took up commercial singing guided by Mr. Prabir Karmakar and Mr. Buddhadeb Ganguly (stalwart music composer and guitarist).  He also underwent training in Classical and semi classical music under Pt.  Jayanta Sarkar, Rabindra Sangeet under Pt.  Agnibho Banerjee and Mr Anutosh Chatterjee.  Taking his inclination towards instruments to the next level he pursued learning Table under the legendary Tabla Guru Pt.  Sujit Saha and Guitar under the immensely respected Mr. Amyt Datta. Jackie Chan is a prolific singer, having started producing records in the early 80s.  He started singing the theme songs over the closing credits of his films in 1980, when the film "The Young Master" was produced.  Chan sang its theme song, titled "Kung Fu Fighting Man" entirely in English.  Since then he has produced over 20 different albums, singing over 100 songs in over five languages, and has teamed up with singers such as Emil Chau and the late Anita Mui.  His personal achievements also include winning Best Foreign Singer Award in Japan in 1984.
Answer: Al Jolson