A 28-year-old male presents with a 3-week history of an itchy rash on his trunk and arms. On examination, he has well-demarcated lesions with a characteristic ring-shaped appearance, as shown in the diagram marked **A**. The lesion demonstrates a raised, erythematous, scaly border with central clearing. KOH microscopy of scrapings from the active border reveals branching septate hyphae. Which of the following is the most likely causative organism?