**Core Concept**
Meningococcal meningitis is a severe infection caused by *Neisseria meningitidis*, requiring prompt antibiotic treatment. The patient's allergy to **penicillin** necessitates an alternative antibiotic.

**Why the Correct Answer is Right**
Since the correct answer is not provided, let's consider a common alternative to penicillin in such cases, which would be a **third-generation cephalosporin** like **ceftriaxone** or a **fluoroquinolone**. These classes of antibiotics are effective against *Neisseria meningitidis* and can be used in patients allergic to penicillin, provided the allergy is not to a broad spectrum of beta-lactam antibiotics.

**Why Each Wrong Option is Incorrect**
**Option A:** Without knowing the specific option, a common incorrect choice might be an antibiotic ineffective against *Neisseria meningitidis* or one that cross-reacts with penicillin allergies.
**Option B:** Similarly, this could be another antibiotic that either doesn't cover the causative organism or isn't suitable for patients with penicillin allergies.
**Option C:** This might be an antibiotic with a different spectrum of activity, not ideal for meningococcal meningitis.
**Option D:** Could be an antibiotic that, while effective against some bacteria, is not the best choice for someone with a penicillin allergy and meningococcal meningitis.

**Clinical Pearl / High-Yield Fact**
In patients with a penicillin allergy, it's crucial to consider the severity of the allergy and whether it includes other beta-lactam antibiotics. For meningococcal meningitis, ensuring the chosen antibiotic covers *Neisseria meningitidis* is critical.

**Correct Answer:** Correct Answer: D. Ceftriaxone.