题目内容：
回答题An Early Form of Jazz Music
Music comes in many forms; most countries have a style of their own. At the turn of the last century, _____(51)jazz was born , America had no prominent_____(52)of its own. No one knows exactly when was invented or by whom. But it began to be _____(53)in the early 1890s. Jazz is America's contribution to_____(54)music. In contrast to classical music, which_____(55)formal European traditions, jazz is spontaneous and free in form. It bubbles with energy, _____(56)the moods, interests, and emotions of the people. In the' 1920s jazz_____(57)like America. And so it does today. The_____(58)of the music are as interesting as the music itself. American Negroes, or blacks, as they are called today, were the jazz pioneers. They were brought to the Southern states_____(59)slaves. They were sold to plantation owners and forced to work long hours. When a Negro died his friends and relatives_____(60)a procession to carry to body to the cemetery. In New Orleans, a band often accompanied the_____(61). On the way to the cemetery the band played slow, solemn music, suited to the occasion. _____(62)on the way home the mood changed. Spirits lifted. Death had removed one of their number, but the living were glad to be_____(63). The band played_____(64)music, improvising on both the harmony and the melody of the tunes_____(65)at the funeral. This music made everyone want to dance. It was an early form of jazz.
【题干】_____ A．while
B．when
C．since
D．as
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