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
Which of the following is not a premalignant condition oral cancer- 
Select and explain. 
A. Leukoplakia, B. Erythroplakia, C. Oral submucous fibrosis, D. Systemic Sclerosis
D: Systemic Sclerosis
Answer: D: Systemic Sclerosis 
Explanation: Ans. is 'd' i.e., Systemic Sclerosis Lesions with increased risk of malignancy in oral cancero Premalignant condition:- Leukoplakia, Erythroplakia, Speckled erythroplakia, chronic hyperplastic candidiasiso Conditions increasing risk:- Oral submucous fibrosis, syphilitic glossitis, sideropenic dysphagia (Peterson Kelly syndrome).o Risk is doubtful:- Oral lichen planus, DLE, Dyskeratosis congenita.