**Core Concept**
Spreading streptococcal cellulitis is a type of bacterial infection caused by Group A beta-hemolytic Streptococcus (GABHS), characterized by rapid progression and potential for severe complications, including sepsis and necrotizing fasciitis. Effective treatment involves addressing the infection with antibiotics and supportive care.

**Why the Correct Answer is Right**
The primary treatment for spreading streptococcal cellulitis involves broad-spectrum antibiotics that target GABHS, such as penicillin or clindamycin. These antibiotics work by inhibiting cell wall synthesis, ultimately leading to bacterial death. In severe cases, surgical debridement may be necessary to remove infected tissue and prevent further spread. Prompt initiation of antibiotics is crucial to prevent complications and reduce morbidity.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because antiviral medications are not effective against bacterial infections like streptococcal cellulitis.
**Option B:** This option is incorrect because corticosteroids, while sometimes used to reduce inflammation, are not a primary treatment for bacterial infections.
**Option C:** This option is incorrect because antifungal medications are not effective against bacterial infections like streptococcal cellulitis.

**Clinical Pearl / High-Yield Fact**
It's essential to recognize the signs of spreading streptococcal cellulitis, which can include rapid progression of symptoms, severe pain, and a characteristic "striped" appearance of the affected area. Prompt recognition and treatment can significantly reduce the risk of complications and improve patient outcomes.

**Correct Answer:** C. Clindamycin