Which of the following laboratory tests is used to diagnose and monitor the response to treatment in patients with megaloblastic anemia?

A Reticulocyte count
B Serum lactate dehydrogenase (LDH) level
C Peripheral blood smear ✓
D Bone marrow biopsy

Explanation

A peripheral blood smear can help diagnose megaloblastic anemia by showing characteristic large, abnormal red blood cells.

Source

Wintrobe's Clinical Hematology
Hematology Hematology: Anemia Hematology: Anemia Easy MEDICAL Confidence: high