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: Skin
Koplik spots are pathognomic of ? 
Select and explain. 
A. Measles, B. Diphtheria, C. Donovanosis, D. Gonorrhoea
A: Measles
Answer: A: Measles 
Explanation: Ans. is 'a' i.e., Measles Koplik spots Koplik spots, the pathognomonic enanthem of measles, begin as small, bright red macules that have a 1-2-mm blue- white speck within them. They are typically seen on the buccal mucosa near the second molars in 1-2 days before and lasting 2 days after the onset of the rash.