Which of the Following Statements Is Incorrect Regarding the Microbiome

Which of the following statements is incorrect regarding the microbiome of the gastrointestinal tract?

A) The gut microbiome,while playing an important role in gastrointestinal function,does not influence other systems in the body.
B) Many organisms of the microbiome are commensals but others are mutualistic; they synthesize important molecules,such as vitamins,that humans cannot make themselves.
C) The GI microbiome plays a role in "teaching" the immune system how to recognize and react to foreign cells.
D) The gut microbiome plays a protective role by preventing the growth of pathogens through microbial antagonism.