Mikhaila is a 7-month-old infant who is consuming about 30 ounces of milk per day in addition to soft, fresh fruit and soft-cooked vegetables. When her hemoglobin is tested, the doctor reports a lower than normal value. What is the most likely cause of her low hemoglobin? 1) Iron deficiency 2) Vitamin C deficiency 3) Calcium deficiency 4) Protein deficiency