This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Hemodynamics, Subject name: Pathology
Which virus leads to Aplastic Crisis? 
Select and explain. 
A. Poxvirus, B. Parvo virus B19, C. Hepatitis A, D. Hepatitis B
B: Parvo virus B19
Answer: B: Parvo virus B19 
Explanation: * Hepatitis B, C and D can lead to aplastic anaemia. In contrast Parvo virus B19 leads to a transient bone marrow illness called aplastic crisis.* Parvovirus B19 (B19V) is a single-stranded DNA virus of the family Parvo-viridae and genus Erythrovirus.* It has a unique tropism for human erythroid progenitor cells. The virus requires the P blood antigen receptor (also known as globoside) to enter the cell.