## Core Concept
Meningitis caused by *Neisseria meningitidis* is a severe and potentially life-threatening infection. Chemoprophylaxis is considered for close contacts of individuals with meningococcal disease to prevent secondary cases. The goal is to eliminate nasopharyngeal carriage of *N. meningitidis* in these individuals.

## Why the Correct Answer is Right
The correct answer involves understanding who is considered a close contact and thus at higher risk of acquiring the infection. Close contacts include individuals who have been in close proximity (usually within 3 feet) to the infected person, especially in enclosed environments like dormitories. This typically includes roommates, individuals who share food or utensils, or anyone directly exposed to the infected person's respiratory secretions. Chemoprophylaxis is recommended for these individuals to reduce their risk of developing the disease.

## Why Each Wrong Option is Incorrect
- **Option A:** This option might not specifically target the individuals at highest risk, such as those living in close quarters within the dormitory.
- **Option B:** Similar to Option A, this might not accurately reflect the group at highest risk based on their exposure to the infected individuals.
- **Option C:** This option could potentially include individuals who are not at significant risk, diluting the effectiveness of chemoprophylaxis by treating those who are less likely to be exposed.

## Clinical Pearl / High-Yield Fact
A key point to remember is that chemoprophylaxis for *Neisseria meningitidis* is typically recommended for close contacts within a 3-foot radius, especially in enclosed spaces. The antibiotic of choice is often rifampin, ciprofloxacin, or ceftriaxone, depending on the patient's age and other factors. This preventive measure is crucial in outbreak settings or for individuals with specific exposures.

## Correct Answer: D.