Final answer:
The sudden death of a college student with acute febrile illness and headache, accompanied by a petechial rash, is most likely due to meningococcal meningitis, which can lead to septic shock and rapid death.
Step-by-step explanation:
The most likely explanation for the sudden death of a 20-year-old college student with a history of an acute febrile illness, headache, and skin rash would be C. meningococcal meningitis. The clinical presentations of high fever, headache, body aches, alongside a characteristic petechial rash and the possibility of rapid progression to death align with the symptoms caused by Neisseria meningitidis, the bacterium responsible for meningococcal meningitis. This condition is associated with severe complications such as septic shock, disseminated intravascular coagulation, and can lead to death within a few hours if untreated.