This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Anatomy
The whiff test is useful in the diagnosis of 
Select and explain. 
A. Trichomonas, B. Bacterial vaginosis, C. Candida, D. PID
B: Bacterial vaginosis
Answer: B: Bacterial vaginosis 
Explanation: Bacterial vaginosis AMSEL criteriaNugent criteriaThin, white, yellow, homogeneous discharge.Clue cells on microscopy.pH of vaginal fluid >4.5.Release of a fishy odor on adding alkali--10% potassium hydroxide (KOH) solution (Whiff test)At least three of the four criteria should be present for a confirmed diagnosis.Grade 1 (Normal): Lactobacillus morphotypes predominate.Grade 2 (Intermediate): Mixed flora with some Lactobacilli present, but Gardnerella or Mobiluncus morphotypes also present.Grade 3 (Bacterial Vaginosis): Predominantly Gardnerella and/or Mobiluncus morphotypes. Few or absent Lactobacilli.(Refer: Novak's Textbook of Gynaecology, 23rd edition)