Microbiology A patient is suffering from pneumonia. Laboratory study shows acid-fast filamentous bacterium. The causative organism is ? A M. tuberculosis B Actinomyces C Nocardia D Mycobacterium Avium intracellulare 💡 Explanation A patient is suffering from pneumonia. Laboratory study shows acid-fast filamentous bacterium. The causative organism is ? ✓ Correct Answer: C. Nocardia