In AIDS patient presenting with fever, cough a diagnosis of pneumocystin pneumonia is best established by

Ans. is 'b' i.e., Bronchoalveolar lavage Diagnosis of PCP requires Demonstration of the organism in samples obtained from induced sputum. Bronchoalveolar lavage, transbronchial biopsy, or open-lung biopsy. If the histological examination fails :? u PCR is required to make the diagnosis