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: Pathology
Leucocytopenia is seen in 
Select and explain. 
A. influenza, B. agranulocytosis, C. liver cirrhosis, D. all of the above
D: all of the above
Answer: D: all of the above 
Explanation: None