Which of the following antifungal medications is commonly used to treat skin fungus?

Clotrimazole is commonly used to treat skin fungal infections due to its broad antifungal activity, especially against dermatophytes and yeast. It is an imidazole antifungal that works by inhibiting the synthesis of ergosterol, a key component of fungal cell membranes, thereby disrupting their function and leading to cell death. Clotrimazole is often applied topically in the form of creams or powders, making it particularly suited for treating conditions like athlete's foot, jock itch, and ringworm.

Amphotericin B, while an effective antifungal, is primarily reserved for serious systemic fungal infections and is not the first choice for localized skin infections. Levofloxacin is an antibacterial agent that does not have antifungal properties and is instead used to treat bacterial infections. Vancomycin, like levofloxacin, is an antibiotic meant for severe bacterial infections, particularly those caused by Gram-positive organisms. Therefore, the specific action and application of clotrimazole make it the appropriate choice for treating skin fungal infections.