Question

what will most likely happen if a person does not consume the minimum daily requirements of carbohydrates

Answer 1

their body might break down lipids instead of carbohydrates causing the person to lose weight or become malnourished after a period of time

Answer 2

Carbohydrates supply a long supply of energy for a long time so if he does not eat carbohydrates he will be very tired and lacking in energy.
Moreover if does not eat carbs for a long time his body would start rejecting food(vomiting or throwing up)