**Core Concept**
Fungal meningitis in immunocompromised individuals is a serious infection affecting the protective membranes covering the brain and spinal cord. It is caused by opportunistic fungal pathogens that take advantage of a weakened immune system.

**Why the Correct Answer is Right**
The most common causative agent of fungal meningitis in immunocompromised individuals is *Cryptococcus neoformans*. This pathogen typically enters the body through inhalation of spores and then invades the central nervous system, leading to meningitis. The virulence of *C. neoformans* is attributed to its ability to evade the host immune response and adhere to the meninges, causing inflammation and damage.

**Why Each Wrong Option is Incorrect**
**Option A:** Aspergillus species can cause invasive aspergillosis, particularly in immunocompromised patients, but it is not the most common cause of fungal meningitis.

**Option B:** Histoplasma capsulatum can cause histoplasmosis, which may involve the central nervous system, but it is not the primary cause of fungal meningitis in immunocompromised individuals.

**Option C:** Candida species are opportunistic pathogens that can cause a range of infections, including meningitis, but they are not the most common cause of fungal meningitis in immunocompromised patients.

**Clinical Pearl / High-Yield Fact**
Immunocompromised patients, particularly those with HIV/AIDS, are at increased risk of developing cryptococcal meningitis, which is often characterized by a gradual onset of symptoms, including headache, fever, and altered mental status.

**Correct Answer:** C. Cryptococcus neoformans.