A 13-year-old diagnosed with absolute beta-cell destruction will most appropriately be treated initially with which approach and why?

Intermittent high-protein, low-carbohydrate diet with no need for insulin because dietary changes eliminate the hyperglycemic effect of food entirely in type 1 diabetes.

Lifelong exogenous insulin replacement, because autoimmune beta-cell destruction results in negligible endogenous insulin production that cannot be reversed by lifestyle modification.

Oral insulin-sensitizing medications as first-line therapy because they replace insulin function without injections and restore beta-cell mass.

Lifestyle modification alone (calorie restriction and exercise) that usually restores endogenous insulin secretion within months in adolescents with autoimmune beta-cell destruction.