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: Surgery
Precancerous lesion of the larynx include: 
Select and explain. 
A. Keratosis laryngis, B. Laryngis sicca, C. Scleroma, D. All of the above
A: Keratosis laryngis
Answer: A: Keratosis laryngis 
Explanation: None