This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory system, Subject name: Pediatrics
The main infectious agent associated with recurrent pulmonary infections in patients with cystic fibrosis is _____________ . 
Select and explain. 
A. Mycoplasma, B. Pseudomonas, C. Pneumocystis, D. Aspergilus
B: Pseudomonas
Answer: B: Pseudomonas 
Explanation: Pseudomonas affect small children with malnutrition and poor immunity.it colonise airway of patients with cysticfibrosis and cause recurrent pulmonary exacerbations. pathology:well demarcated areas of consolidation and necrosis occur due to vasculitis Ref : ESSENTIAL PEDIATRICS ,O.P.GHAI, PG NO:355,7 th edition