Final answer:
George Gershwin refined his musical skills in New York City, particularly during the jazz-rich 1920s, drawing inspiration from venues like the Savoy Ballroom and the Apollo Theater in Harlem.
Step-by-step explanation:
George Gershwin, an illustrious American composer, honed his craft predominantly in New York City. It was here, in the hustle and bustle of the early 20th century, that Gershwin drew inspiration from the wide array of cultural influences prevalent in the city's vibrant music scene. During the 1920s, New York, and particularly the neighborhood of Harlem, was the heart of the jazz movement. Iconic venues such as the Savoy Ballroom and the Apollo Theater were the epicenters of this musical revolution where influential jazz figures merged diverse styles into a distinctly American sound that Gershwin incorporated into his work.
Answer: B) New York