单选题 Music comes in many forms; most countries have a style of their own. 1 the turn of the century when jazz was born, America had no prominent style of its own. No one knows exactly when jazz was 2 , or by whom. But it began to be heard in the early 1900s. Jazz is America"s contribution to 3 music. In contrast to classical music, which follows formal European traditions, jazz is spontaneous and free form. It bubbles with energy, 4 the moods, interests, and emotions of the people. In the 1920s jazz sounded like America, and 5 it does today. The origins of this music are as interesting as the music 6 . American Negroes, or blacks, as they are called today, were the jazz pioneers. They were brought to Southern States 7 slaves. They were sold to plantation owners and forced to work long hours. When a Negro died his friend and relatives 8 a procession to carry the body to the cemetery. In New Orleans, a band often accompanied the procession. On the way to the cemetery the band played slow, solemn music suited to the occasion. 9 on the way home the mood changed. Spirits lifted. Death had removed one of their relations, but the livings were glad to be alive. The band played 10 music, improvising(即兴表演) on both the harmony and the melody of the tunes presented at the funeral. This music made everyone want to dance. It was an early form of jazz.