Which of the Following Statements Regarding the Microbiome of the Nervous

Which of the following statements regarding the microbiome of the nervous system is true?

A) In the healthy state,the nervous system is believed to be free from microorganisms.
B) In its latent state,the herpesvirus is considered to be part of the microbiome of the nervous system.
C) The nervous system develops without any influence from microbes inhabiting other tissues.
D) Defense mechanisms of the CNS include competition for nutrients and space between pathogens and the normal microbiota within the tissues.