Gross Anatomy USMLE Step 1 Practice Question

A 47-year-old man presents to the emergency department 1 hour after a straddle injury sustained when he fell across a fence rail while trimming branches. He reports acute perineal and scrotal pain. Vital signs are stable: BP 128/82 mmHg, HR 88 bpm, RR 16. On examination, there is gross hematuria with blood at the urethral meatus, significant perineal ecchymoses, and a rapidly expanding scrotal hematoma. Abdominal and rectal examinations are unremarkable. Pelvic radiograph demonstrates soft tissue swelling but no fractures. Which of the following urethral segments is most likely to have sustained traumatic injury?