Final answer:
c. DJ Kool Herc's party in the South Bronx is widely credited as marking the "birth" of hip-hop.
Step-by-step explanation:
The event widely credited as marking the "birth" of hip-hop is c. DJ Kool Herc's party, option C. In the 1970s, DJ Kool Herc, a Jamaican-American DJ, hosted a party in the South Bronx, New York, where he introduced a technique called "breakbeat" mixing.
This involved extending the instrumental section of a song, known as the break, to allow dancers more time to showcase their moves. DJ Kool Herc's innovative approach to DJing and his party became influential in the development of hip-hop music, culture, and the use of turntables.