Two years ago, a 30-year old lady had undergone near total thyroidectomy for papillary carcinoma. During the follow up visits, she was found to have multiple, discrete, mobile, left, deep cervical lymph nodes measuring 1 to 1.5 cms in size. the ideal treatment for this lady would be -
Iodine 131 ablation
External irradiation to the neck
Thyroxine therapy
Modified redical neck dissection