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
[{'content': 'True about aphthous ulcer -a) Viral predispositionb) Recurrent ulcerc) Deep ulcersd) Involves the mucosa of the hard palatee) Steroids given as treatment \nSelect and explain. \nA. abe, B. bcd, C. cde, D. acd', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Aphthous ulcer (Canker sores) \n\nAphathous ulcers are small ulcer craters in the lining of mouth that are frequently painful and sensitive.\nExact etiology is not known; it may be autoimmune process, nutritional deficiency (vitamin B1„ folic acid, iron), viral or bacterial infection, food allergies or due to hormonal changes or stress.\nAphathous ulcers typically starts in childhood or adolescence.,\nCharacterized by recurrent, small, round or oval ulcers with circumscribed margins, erythematous haloes, and yellow or gray floor.\nThey resolved spontanously in third decade.\nThe lesiosn may be single or multiple and usually involve movable mucosa, i.e., inner surface of lips, buccal mucosa, tongue, floor of mouth and soft palate, while sparing mucosa of hard palate and gingivae.\n\n\u200bTreatment : \xa0- If lesions do not resolve spontaneously, topical steroid and cauterization of base with 10% silver nitrate can be tried. In severe cases tetracycline mouth rinse can be given. For pain lignocaine viscous may be used.', 'role': 'assistant'}]