Final answer:
The gut microbiome can impact a person's nutrition by affecting appetite regulation and providing a source of energy through fermentation of carbohydrates.
Step-by-step explanation:
b) It affects appetite regulation. The gut microbiome plays a significant role in nutrition, influencing various aspects of digestion, nutrient absorption, and metabolism. Option b, "It affects appetite regulation," is particularly relevant. The composition of the gut microbiome can influence the production of certain signaling molecules and hormones that communicate with the brain, affecting appetite and food cravings. Imbalances in the gut microbiota have been associated with conditions like obesity and metabolic disorders, suggesting a link between the microbiome and appetite regulation.