A 3-year-old girl with Turner syndrome (45, X) presents to clinic for routine evaluation. Her parents report she becomes tired quickly during play and has had several upper respiratory infections in the past year. On examination, blood pressure in the right arm is 128/85 mmHg, while in the right leg it is 92/58 mmHg. Femoral pulses are diminished bilaterally and delayed compared to brachial pulses. A systolic ejection murmur is heard at the left infraclavicular region. Chest radiograph shows mild left ventricular hypertrophy and rib notching. Echocardiography reveals a discrete narrowing of the descending thoracic aorta distal to the left subclavian artery with peak gradient of 55 mmHg across the lesion. Which of the following is the most appropriate long-term management?

1. A)Antihypertensive therapy with ACE inhibitors alone and serial follow-up echocardiograms every 6 months
2. B)Beta-blocker therapy to reduce aortic wall stress and prevent dissection
3. C)Observation with activity restriction and regular blood pressure monitoring, as most lesions improve spontaneously
4. D)Surgical repair or endovascular stenting given the significant gradient and hemodynamic burdenGABARITO
5. E)Prostaglandin E1 infusion to maintain ductal patency and reduce the gradient