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: Surgery
Commonest cause of lung abscess - 
Select and explain. 
A. Aspiration, B. Hematogenous spread from distant site, C. Direct contact, D. Lymphatic spread
A: Aspiration
Answer: A: Aspiration 
Explanation: 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.