A nurse is reinforcing teaching about pernicious anemia with a client following a total gastrectomy. Which of the following dietary supplements should the nurse include in the teaching as the treatment for pernicious anemia?

A. Vitamin C is important for iron absorption but does not treat pernicious anemia. B. Iron supplementation treats iron-deficiency anemia, not pernicious anemia. C. Vitamin B12 is essential for treating pernicious anemia, especially after total gastrectomy, because intrinsic factor production is lost, preventing B12 absorption from food. D. Folate deficiency can cause megaloblastic anemia, but supplementation does not correct the B12 deficiency seen in pernicious anemia.