A 37-Year-Old Woman Who Is on Chemotherapy Is Admitted in Respiratory

A 37-year-old woman who is on chemotherapy is admitted in respiratory distress. She had signs of focal central nervous system (CNS) lesions early in the day and is now in a comatose state. Both the CNS and pulmonary biopsies show dichotomously-branching (at an acute angle) , septate hyphae. What is the most likely underlying condition?

A) $CD4^+$ cell count less than 200
B) Ketoacidotic diabetes
C) Multiple myeloma
D) Severe neutropenia
E) Sickle cell disease