**Core Concept**
_Clostridioides difficile_ (C. difficile) infection is a type of bacterial infection that primarily affects the colon, caused by the overgrowth of the bacterium C. difficile. The treatment of C. difficile infection involves the use of antibiotics that target the causative organism and restore the balance of the gut microbiota.

**Why the Correct Answer is Right**
The treatment of C. difficile infection typically involves the use of oral vancomycin, fidaxomicin, or metronidazole. Vancomycin is a glycopeptide antibiotic that inhibits cell wall synthesis in bacteria, whereas metronidazole is a nitroimidazole antibiotic that targets anaerobic bacteria, including C. difficile. Bacitracin, an aminoglycoside antibiotic, also has activity against C. difficile. Nitazoxanide is an antiprotozoal agent that has been shown to be effective in treating C. difficile infection by targeting the bacterial cell membrane. The use of multiple antibiotics, including metronidazole, bacitracin, and nitazoxanide, may be considered in certain cases of C. difficile infection, particularly in patients who are allergic to vancomycin or have failed first-line treatment.

**Why Each Wrong Option is Incorrect**
**Option A:** Metronidazole is a correct treatment option for C. difficile infection, making this option incorrect.
**Option B:** Bacitracin is not a standard treatment for C. difficile infection, although it may have some activity against the bacterium.
**Option C:** Nitazoxanide is not typically used as a first-line treatment for C. difficile infection, but it may be considered in certain cases.

**Clinical Pearl / High-Yield Fact**
When treating C. difficile infection, it is essential to address the underlying cause of the infection, such as the use of broad-spectrum antibiotics, and to restore the balance of the gut microbiota through the use of probiotics or fecal microbiota transplantation.

**✓ Correct Answer: D. All of the above**