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: Unknown
[{'content': 'Frequent blushing (“erethism”) is associated with : - \nSelect and explain. \nA. Mercury, B. Lead, C. Phenolic acid, D. Carbolic acid', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Mercury\nMechanism of toxicity.\nMercury reacts with sulfhydryl (SH) groups, resulting in enzyme inhibition and pathologic alteration of cellular membranes.\nClinical presentation. Acute inhalation\nSevere chemical pneumonitis and noncardiogenic pulmonary edema.\nAcute gingivostomatitis may also occur.\nChronic intoxication\nClassic triad\nNeuropsychiatric disturbances\nGingivostomatitis. Metallic taste\nFrequent blushing (“erethism”).\nPain in the extremities,often accompanied by pinkish discoloration and desquamation (“pink disease”)\nReference – Poisoning & Drug Overdose by Kent R. Olson 3th- 213', 'role': 'assistant'}]