**Core Concept**
Meningococcal meningitis is a severe infection caused by the bacterium *Neisseria meningitidis*. It primarily affects the meninges, the protective membranes covering the brain and spinal cord. The disease is characterized by its rapid progression and high mortality rate if not treated promptly.

**Why the Correct Answer is Right**
The correct answer is related to the pathophysiology of meningococcal meningitis. *Neisseria meningitidis* invades the meninges by adhering to the epithelial cells lining the nasopharynx and then enters the bloodstream, causing a severe inflammatory response. The bacteria produce endotoxins that trigger an overwhelming release of cytokines, leading to vasculitis and inflammation of the meninges.

**Why Each Wrong Option is Incorrect**
**Option A:** This option might be incorrect as it's not directly related to the pathophysiology of meningococcal meningitis. However, the exact wording is missing, so it's hard to determine.

**Option B:** This option might be incorrect as it's not specific to meningococcal meningitis. However, the exact wording is missing, so it's hard to determine.

**Option C:** This option is incorrect as the disease is primarily caused by *Neisseria meningitidis*, not *Streptococcus pneumoniae*. While *Streptococcus pneumoniae* is another common cause of bacterial meningitis, it's not the primary pathogen in meningococcal meningitis.

**Clinical Pearl / High-Yield Fact**
Meningococcal meningitis is a medical emergency that requires prompt treatment with antibiotics, such as ceftriaxone or cefotaxime, and supportive care, including fluid resuscitation and respiratory support. Vaccination is also an effective measure to prevent the disease, particularly in high-risk populations.

**Correct Answer:** C. *Neisseria meningitidis* is the primary cause of meningococcal meningitis.