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: Surgery
Best investigation for prostate cancer is - 
Select and explain. 
A. Prostate Specific Antigen, B. Acid Phosphatse, C. PSA velocity, D. Alkaline phosphatase
C: PSA velocity
Answer: C: PSA velocity 
Explanation: Answer- C. PSA velocityFor men with a PSA above 4, PSA velocity of more than .75 ng/ml year is suggestive of Ca.While for those with lower PSA levels, rates above 0.5 ng/ml per year should be used to advise biopsy.