This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Lab Investigations, Subject name: Microbiology
All are true about Bacterial vaginosis except 
Select and explain. 
A. Vaginal pH <4.5, B. Nugent scoring can be used for diagnosis, C. Fishy smelling discharge after addition of KOH, D. Presence of clue cells is pathognomic
A: Vaginal pH <4.5
Answer: A: Vaginal pH <4.5 
Explanation: Amsel's criteria is used for diagnosis of bacterial vaginosis although Nugent scoring can also be used Amsel's criteria Vaginal pH> 4.5 Discharge when put in 10 % KOH produces fishy smell Clue cells are seen Clue cells are vaginal squamous epithelial cells coated with Gardnerella vaginalis