Number two, it's the LAST voice, of black people
He specifies that it is the last voice of black people which could have two possible meanings.
It is the last voice of the black people because it is essentially a desperate plea for help to escape the situation they are in. Making it big in rap gets you out of the streets.
It is the last voice because it is the culmination of years of African music. Hip hop is heavily influenced by soul and jazz, two types of African American music. Rap/Hip Hop has perfected African American music
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