Final answer:
Benny Goodman, an American jazz musician, was known as the 'King of Swing'. He played a key role in promoting and popularizing swing music during the 1930s and 1940s.
Step-by-step explanation:
The 'King of Swing' is C) Benny Goodman. Benny Goodman was an American jazz musician, known for his clarinet work and leadership of one of the most popular big bands in the Swing Era during the 1930s and 1940s. He earned the nickname, 'King of Swing' for his pivotal role in promoting and popularizing swing music.
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