This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Ophthalmology
Incubation period of gonococcal ophthalmia neonatorum is: 
Select and explain. 
A. 24 hours, B. 5-7 days, C. 7-10 days, D. None of the above
D: None of the above
Answer: D: None of the above 
Explanation: Ans. None of the above