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: ENT
Which of the following is precancerous lesion - 
Select and explain. 
A. Pachydermia of larynx, B. Laryngitis sicca, C. Keratosis of larynx, D. Scleroma larynx
C: Keratosis of larynx
Answer: C: Keratosis of larynx 
Explanation: Lichen planus has no malignant potential.

Papilloma– “The malignant transformation from benign non keratining squamous papilloma to squamous cell carcinoma can occur in children, but is rarely seen” 
Leukoplakia is a white patch, in which there is epithelial hyperplasia along with atypical cells. It is a premalignant condition. Another name for leukoplakia is hyperkeratosis dyskeratosis
Smoking is a predisposing factor, not a premalignant condition. y In some cases of chronic laryngitis, the laryngeal mucosa becomes dysplastic particularly over true vocal folds and is a premalignant condition.
Chronic inflammatory conditions of larynx like chronic laryngitis may develop into malignancy.

Keratosis of larynx/leukoplakia:- 
It is epithelial hyperplasia of the upper surface of one or both vocal cords.

Appears as a white plaque or warty growth on cord without affecting its mobility
Regarded as a precarcerous condition as Ca in situ develops frequently
T/t = stripping of cords