**Core Concept**
The question is testing the understanding of the pathogenesis of neonatal meningitis, particularly the role of maternal genital tract infections in the etiology of this condition. Congenital infections can occur when pathogens cross the placenta or are transmitted during delivery, leading to infection in the neonate.

**Why the Correct Answer is Right**
The correct answer is Group B Streptococcus (GBS). GBS is a common cause of neonatal meningitis and sepsis. The bacteria can colonize the maternal genital tract, and vertical transmission can occur during delivery, leading to infection in the neonate. This is often due to the bacteria's ability to adhere to and invade the epithelial cells lining the birth canal, leading to a breach in the maternal-fetal barrier.

**Why Each Wrong Option is Incorrect**
* **Option A:** Escherichia coli (E. coli) is a common cause of neonatal sepsis but is less commonly associated with meningitis in this age group.
* **Option B:** Listeria monocytogenes is a rare but serious cause of neonatal meningitis, but it is not typically associated with maternal genital tract colonization.
* **Option D:** Candida species are common causes of neonatal candidiasis, but they are not typically associated with meningitis in this age group.

**Clinical Pearl / High-Yield Fact**
GBS colonization in the maternal genital tract is a significant risk factor for neonatal meningitis. A maternal GBS screening test is recommended at 35-37 weeks of gestation, and intrapartum antibiotic prophylaxis is recommended for GBS-colonized women at the onset of labor.

**Correct Answer: C. Group B Streptococcus**