Which ONE of the following was a true and genuine mark of Stravinsky's acceptance into the USA and its cultural life?

Igor Stravinsky was certainly among the few most remarkable musicians to bestride the 20th century, in which the writing and making of music changed more than ever before. Stravinsky wrote many different types of work including operas, ballets, symphonies, concertos, chamber music and choral works. His career last for more than 60 years and he died in 1971 at the age of 88.