question: A 50-year-old man presents with paresthesia. HB-6.8g/dl. Peripheral smear shows macrocytosis and neutrophils with hypersegmented nuclei.endoscopy reveals atrophic gastritis. a most probable diagnosis is
opa: Folate deficiency
opb: Vitamin B12 deficiency
opc: Riboflavin deficiency
opd: Iron deficiency