Which of the following is essential in the lifelong management of a child with congenital adrenal hyperplasia (CAH)?

Rationale: A. Administering thyroid hormone replacement: Thyroid hormone therapy is indicated for hypothyroidism, not congenital adrenal hyperplasia. CAH is related to impaired adrenal hormone production, so replacing thyroid hormone would not address the underlying issue. B. Regular blood glucose monitoring and insulin therapy: This is a mainstay in the management of diabetes mellitus, not CAH. While adrenal insufficiency can influence glucose regulation, insulin therapy is not a primary treatment unless there is coexisting diabetes. C. High-protein diet to promote growth: Adequate nutrition is important for all children, but a high-protein diet alone does not correct the hormonal deficiencies in CAH. Without proper hormone replacement, growth and development will still be impaired. D. Lifelong glucocorticoid (hydrocortisone) and mineralocorticoid (fludrocortisone) replacement therapy: This is the cornerstone of CAH management, replacing the deficient cortisol and aldosterone to maintain electrolyte balance, blood pressure, and normal metabolism.