A 36 years male presented with complain of productive cough and fever for last 2 months. He has undergone kidney transplantation 2 years back. His sputum examination revealed a gram positive filamentous bacteria that showed acid fastness with modified Ziehl-Neelsen staining (1% H2SO4). The most likely etiological agent is ?
Ans. is 'b' i.e., Nocardia asteroides
Actinomyces israelii
Nocardia asteroides
Blastomyces dermaiiiidis
Crfptosperidium parvum