This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Fungal infections, Scabies, Pediculosis, Subject name: Dental
[{'content': 'Causative agent of Black piedra \nSelect and explain. \nA. Trichosporon beigelii, B. Trichosporon asahii, C. Piedra hoae, D. Trichosporon cutaneum', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Piedra * Superficial infection of hair shaft where fungal elements adhere to form nodes along hair shaft. Two types: black piedra and white piedra . * Black piedra:- Caused by Piedraia hoae; presents with tiny dark concretions on hairs shafts distributed irregularly; culture shows black velvety colony. * White piedra:- Trichosporon cutaneum (formerly T. beigelii) most common; other species include T. ovoides, T. inkin, and T. asahii); presents with light brown, less adherent nodules coating hair shaft (beard, axilla, pubic hairs). * Of note, T. cutaneum can cause fungemia with systemic disease in immunocompromised patients. Treatment:- shaving/cutting hair, topical imidazoles. Ref:- Sima Jain; pg num:- 226', 'role': 'assistant'}]