What Is the Correct Answer to This Question?

A 14 year old boy has complete growth rest of his left proximal tibia after escape boarding injury. He currently has a three millimeter leg length discrepancy, with the left shorter than the right. The correct answer to this question is one observation. A radiograph of the patient's left hand, wrist and fingers, demonstrates a bone age of 14 years. What is the most appropriate management of this patient? And the choices are one observation, two, left tibia lengthening. Three, right tibia epiphysiodesis. Four, right femur epiphysodesis and five, amputation.