PLE-2107

A 60-year-old hypertensive male patient came in for regular follow-up. He has no new complaints, except for easy fatigability and weakness. On examination, there is no hepatomegaly or jaundice, but there is pallor. CBC was ordered, showing a hemoglobin of 9 g/dl with MCV less than 80 fl. Liver function tests and iron studies were all normal. What is the next procedure that should be performed?