This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Poisoning, Subject name: Forensic Medicine
[{'content': 'Yellow discoloration of skin and mucosa is seen in which poisoning? \nSelect and explain. \nA. Nitrous oxide, B. Nitric acid, C. Sulphuric acid, D. Phosphoric acid', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Nitric Acid Synonyms: Aqua Fois, Red Spirit of Nitre Propeies * Clear, colourless, fuming liquid * Pungent odour * With organic substances, it causes yellowish discolouration due to xanthoproteic reaction. Fatal dose: 10 to 15 ml Fatal period: 12 to 24 hours. Autopsy Findings * Corrosion of skin, angle of mouth, lips, mucosa with yellowish discolouration * Stomach wall is soft and friable, ulcerated. * Perforation is less common. REF;THE SYNOPSIS OF FORENSIC MEDICINE:KS NARAYANA REDDY;PAGE NO 298', 'role': 'assistant'}]