This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cardio thoracic surgery  , Subject name: Anatomy
[{'content': 'Commonest cause of lung abcess - \nSelect and explain. \nA. Hematogenous spread from distant site, B. Direct contact, C. Aspiration, D. Lymphatic spread', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Routes of infection to lung Aspiration of organisms that colonize the oropharynx (MC) Inhalation of infections, aerosols Hematogenous dissemination from an extrapulmonary site. Direct inoculation (as in tracheal intubation or stab wounds) Contiguous spread from an adjacent site of infection. Ref : Harrison 17/e p1631', 'role': 'assistant'}]