A 56-year-old woman presents with new fatigue. Hb is 88 g/L, mean corpuscular volume 70 fL, and ferritin 5 µg/L. She has no menorrhagia and is postmenopausal. According to Canadian practice, what is the most appropriate next diagnostic step?AStart oral iron and review in 6 months without further investigationBOrder colonoscopy to evaluate for occult gastrointestinal blood lossCOrder bone marrow biopsyDOrder CT scan of the abdomen and pelvisEAssume dietary iron deficiency and provide dietary counselling onlyCheck my answer