This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Infections and Inflammatory Conditions, Subject name: ENT
Which one of the following conditions is considered to be definitely precancerous in the larynx? 
Select and explain. 
A. Vocal nodules, B. Subglottic hemangiomas, C. Leukoplakia, D. Vocal polyp
C: Leukoplakia
Answer: C: Leukoplakia 
Explanation: (c) Leukoplakia(Ref. Cummings, 6th ed., 1609)Rest are not precancerous.Subglottic hemangiomas are benign vascular tumours. They are rare as such but can lead to progressive stridor. They are commonly associated with cutaneous hemangiomas (the most common benign skin vascular tumours in children). Most subglottic hemangiomas spontaneously resolve by 5 years of age. If large and progressive they can be excised by CO2 LASER or surgically.