This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
What is not true about polycythemia vera 
Select and explain. 
A. It is a cancerous conditoon, B. Incraese in rbc count, C. Blood viscosity increases, D. Decrease in pcv
D: Decrease in pcv
Answer: D: Decrease in pcv 
Explanation: Polycythemia doest cause decrease in pcv