The Immune System Is Developing During Infancy, Most Effective During

The immune system is developing during infancy, most effective during adulthood, and declining during old age. Examine the composition of the gut microbiome to determine a potential correlation with immune activity.

A) Proteobacteria are the dominant component of the microbiome during the time of greatest immune effectiveness
B) The immune system is least effective in infancy and elderly individuals when Actinobacteria levels are highest
C) The immune system is least effective in infancy and elderly individuals when Firmicutes levels are reduced compared to adulthood
D) The immune system is most effective when Bacteroides is the dominant component of the gut microbiome