Fungal and Parasitic Infections USMLE Step 1 Practice Question

A 32-year-old woman with systemic lupus erythematosus presents to the hospital with a 2-week history of progressive dyspnea, nonproductive cough, and low-grade fever. She has been on prednisone 60 mg daily for the past 3 months for lupus flare. Vital signs show temperature 38.5°C, heart rate 118/min, respiratory rate 26/min, and oxygen saturation 89% on room air. Physical examination reveals fine crackles bilaterally at the lung bases. Chest X-ray demonstrates bilateral interstitial infiltrates with a ground-glass appearance. Laboratory studies show LDH 680 U/L, CD4+ count 85 cells/μL (normal >500), and elevated (1→3)-β-D-glucan. Sputum induction with Gomori methenamine silver staining reveals cup-shaped, bowl-shaped organisms. Which of the following organisms is most likely responsible for this patient's pneumonia?