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
Gaisbock syndrome is known as 
Select and explain. 
A. Primary Familial Polycythemia, B. High Altitude Erythrocytosis, C. Spurious Polycythemia, D. Polycythemia Vera
C: Spurious Polycythemia
Answer: C: Spurious Polycythemia 
Explanation: Answer is C (Spurious Polycythemia) Gaisbock syndrome refers to Spurious Polycythemia or Relative Erythrocytosis due to decreased plasma volume.