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': 'An elderly diabetic has left sided orbital cellulitis, CT scan of paranasal sinuses shows evidence of left maxillary sinusitis. A Gram-stained smear of the orbital exudates shows irregularly branching septate hyphae. The following is the most likely aetiological agent. \nSelect and explain. \nA. Aspergillus, B. Rhizopus, C. Mucor, D. Candida', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e. AspergillusRef.: Harrison 16th/Ep 1190 (15th/Ep 1178); CMDT 2003 p 1489; Anantnarayan 6th/Ep 577 & 578;Jawetz 22nd/e p554Septate hyphae and involvement of sinuses suggest the diagnosis of Aspergillus infection.Aspergillus can cause sinusitis and the hyphae of Aspergillus are septate and branched.About other options;Mucormycosis -Is an invasive fungal infection caused by a fungus of the species Zygomycetes, therefore, it is also known as Zygomycosis.Diabetes is a predisposing factor for Mucormycosis, but remember that all the fungus of the species Zygomycetes has aseptate hyphae.Fungus of the family Zygomycetes includeRhizopusMucorAbsidiaPilolobusCunninghamellaIn Candida, the infectious form is yeast not hyphae", 'role': 'assistant'}]