Once a child is started on oral iron therapy for the treatment of iron-deficiency anemia, what changes are evident in the laboratory studies? A) There is an immediate rise in the reticulocyte count, and the hemoglobin level returns to normal in 2 weeks B) There is a rise in the reticulocyte count beginning on the third day, and the hemoglobin level returns to normal in 6 to 10 weeks C) There is a concurrent rise in the hemoglobin level and the reticulocyte count, with both returning to normal in 3 weeks D) There is a rise in the reticulocyte count beginning in 2 weeks, and the hemoglobin level returns to normal in 3 to 6 weeks