What is significant about George Gershwin's work? his efforts to combine jazz elements and classical forms his breakthrough opera that defied stereotypical portrayals of black Americans his philanthropic work on the Lower East Side his pioneering radio show "Music with George" a & b only b & c only b & d only none of these Question 22 / 2 ptsOne of Ives' most-performed orchestral works is: The Unanswered Question The Concord Sonata