单选题 Music comes in many forms; most countries have a style of their own. (56) the mm of the century when jazz was born, America had no prominent (57) of its own. No one knows exactly when jazz was (58) , or by whom. But it began to be (59) in the early 1900s. Jazz is America's contribution to (60) music. In contrast to classical music, which (61) formal European traditions, jazz is spontaneous and free in form. It bubbles with energy, (62) the moods, interests, and emotions of the people. In the 1920s jazz (63) like America, and (64) it does today. The (65) of this music are as interesting as the music (66) . American negroes, or blacks, as they are called today, were the jazz (67) . They were brought to Southern States (68) slaves. They were sold to plantation owners and forced to work long (69) . When a Negro died his friends and relatives (70) a procession to carry the body to the cemetery. In New Orleans, a band often accompanied the (71) . On the way to the cemetery the band played slow, solemn music suited to 'the occasion. (72) on the way home the mood changed. Spirits lifted. Death had removed one of their (73) , but the living were glad to believe. The band played (74) music, improvising(即兴表演) on both the harmony and the melody of the tunes (75) at the funeral. This music made everyone want to dance. It was an early form of jazz.