A 32-yeаr-оld wоmаn presents tо her primаry care physician for generalized fatigue. She states that she is doing well but that she always feels tired. She started exercising to have more energy, finds that she tires easily, and has not felt motivated to return to the gym. She is doing well and excelling at her job. The patient has a past medical history of uterine leiomyomas (fibroids). Her temperature is 98.8°F, blood pressure is 100/68 mmHg, pulse is 80/min, respirations are 14/min, and oxygen saturation is 98% on room air. Initial laboratory tests are ordered and results as seen below.Hemoglobin: 10 g/dLHematocrit: 32% MCV: 78 µm3 Ferritin: 10 mg/mLTotal iron binding capacity: 620 mcg/dLLeukocyte count: 6,500/mm3 with normal differentialPlatelet count: 190,000/mm3Serum:Na+: 141 mEq/LCl-: 102 mEq/LK+: 4.1 mEq/LHCO3-: 24 mEq/LBUN: 16 mg/dLGlucose: 99 mg/dLCreatinine: 1.1 mg/dLTSH: 3.4 mIU/mLWhich of the following is the most appropriate next step in management?