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': "Microscopic examination of a patient's sputum shows aseptate fungus. Which of the following is an aseptate fungus? \nSelect and explain. \nA. Aspergillus, B. Candida, C. Nocardia, D. Rhizopus", 'role': 'user'}, {'content': 'Answer: D \nExplanation: In biopsy specimens, Rhizopus is seen microscopically as nonseptate hyphae with broad, irregular walls and branches that form more or less at right angles. Cultures show colonies with spores contained within a sporangium. These organisms are transmitted by airborne asexual spores and invade tissues of patients with reduced host defenses. Patients with diabetic ketoacidosis, burns, or leukemia are paicularly susceptible. Ref: Levinson W. (2012). Chapter 50. Oppounistic Mycoses. In W. Levinson (Ed), Review of Medical Microbiology & Immunology, 12e.', 'role': 'assistant'}]