perhaps you dont unerstand what what the term mc is?
let me wiki that for you :
Rapping
In the early 1970s, the term MC became associated with what would change to become known as the rapper in hip-hop / rap music and culture. Originally, the term was simply used as Master of Ceremonies. It's believed that the first musician to call himself an MC was Melle Mel from Grandmaster Flash. Traditionally, an MC uses rhyming verses, whether pre-written or freestyled, to introduce and praise the DJ he or she works with, to hype up the crowd. As hip-hop progressed, the title MC has been thought to mean a number of acronyms such as Microphone Controller, "Microphone Commander", Mic Checka, Music Commentator, and one who Moves the Crowd, notably through Rakim's lyrics on the matter (Eric B. easy on the cut and no mistakes allowed/ Cuz to me, MC means move the crowd). Some use this word interchangeably with the term rapper, but according to many, they should never cross paths.
Uncertainty over the acronym's expansion may be considered evidence for the ubiquity of the acronym: the full master of ceremonies is very rarely used in the hip-hop scene. This confusion prompted the hip-hop group A Tribe Called Quest to include this statement on their 1993 Midnight Marauders album:
The use of the term MC when referring to a rhymer originates from the dance halls of Jamaica