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: Microbiology
[{'content': 'All of the following are true about Diphtheroids except: \nSelect and explain. \nA. Ferments sucrose, B. Normal commensal in throat, skin, conjuctiva, C. Does not produce toxin, D. Pyrazinamidase test negative', 'role': 'user'}, {'content': 'Answer: D \nExplanation: C.hoffmannii and C.xerosis both are Pyrazinamidase positive.', 'role': 'assistant'}]