Final answer:
Calcium supplements will be required as a result of avoiding lactose in the diet.
Step-by-step explanation:
Lactose intolerance is a condition in which the lactose in milk cannot be digested well in the small intestine. To avoid lactose in the diet, supplements are required to ensure proper nutrition. In this case, the nurse tells the mother that calcium supplements will be required because avoiding lactose means avoiding dairy products, which are a rich source of calcium.