Seizures Bring a 24-Year-Old Man to the Emergency Department

Seizures bring a 24-year-old man to the emergency department. He's had a growing fever, headache, and vomiting for two days. A physical examination reveals evidence of meningeal inflammation. Despite extensive medical care, the patient quickly goes unconscious and dies 48 hours later. An autopsy reveals clogged leptomeninges with fibrinopurulent exudate (not shown) . Numerous ameba are seen in the exudate and brain tissue when examined under a microscope. Which of the following is the most likely pathogen entry route into the CNS?

A) A
B) B
C) C
D) D
E) E