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: ENT
The most common pre-malignant condition of oral carcinoma is: 
Select and explain. 
A. Leukoplakia, B. Erythroplakia, C. Lichen planus, D. Submucous Fibrosis
A: Leukoplakia
Answer: A: Leukoplakia 
Explanation: (a) Leukoplakia(Ref. Cummings, 6th ed., 1299)All the other choices also are pre-malignant but leukoplakia is the most common premalignant condition.