This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Medicine
Pancytopenia may occur in the following except - 
Select and explain. 
A. Megaloblastic anaemia, B. Severe iron-deficiency anaemia, C. Hypoplastic anaemia, D. Paroxysmal nocturnal haemoglobinuria
B: Severe iron-deficiency anaemia
Answer: B: Severe iron-deficiency anaemia 
Explanation: None