This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Oral cavity, Subject name: Surgery
All are premalignant conditions of the oral cavity except? 
Select and explain. 
A. Chronic hyperplastic candidiasis, B. Oral submucosal Fibrosis, C. Snail track ulcer on tongue, D. Sideropenic dysphagia
C: Snail track ulcer on tongue
Answer: C: Snail track ulcer on tongue 
Explanation: Conditions Associated with Malignant Transformation High-risk Lesions Medium-risk Lesions Low-risk or Equivocal-risk Lesions Erythroplakia Speckled Erythroplakia Chronic hyperplastic candidiasis Oral submucous fibrosis Syphilitic glossitis Sideropenic dysphagia \ (Paterson-Kelly syndrome) Oral lichen planus Discoid lupus erythematosus Discoid keratosis congenita Snail track ulcer on tongue: Seen in secondary syphilis , Benign in nature.