Answer: B) Fournier's Gangrene.

Diagnosis: Fournier’s Gangrene: necrotizing fasciitis of the perineum, along with abscess, with inflammation involving the scrotum, prostate, bladder, colon, and anterior abdominal wall
 

Presentation on imaging:

Ultrasound:
Thickened scrotal wall
Gas in scrotum obscuring imaging

CT:

Soft tissue stranding (may be extensive)
Gas within tissues

Asymmetric thickening of fascia 
Abscess may be found
May display cause, such as perianal abscess, fistulous tract, colonic perforation

Imaging of Choice:
Computed Tomography with IV and PO contrast is preferred and diagnostic but only in conjunction with clinical exam
Using lung windows facilitates the ability to see free air outside the lumen of the bowel
Though the diagnosis can be made clinically CT is essential for the surgical team to guide resection

Differential Diagnosis
Cellulitis or abscess of scrotum or perineum
Perianal abscess
Testicular/perianal trauma
Soft tissue edema

Treatment:
Broad Spectrum IV antibiotics, consider double coverage of gram negatives
Emergent debridement, generally by urology/emergency surgery
Fluid resuscitation
NPO for surgery
Resuscitate as you would for any septic patient

Disposition:
Admission, consider intensive care unit depending on patient stability
Often must proceed Level 1 to OR for debridement