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: Social & Preventive Medicine
For the diagnosis of Deep Vein Thrombosis, 2 tests are done together, namely Impedence Plethy smo graphy and leg scanning after injecting 125I fibri nogen. This process will lead to 
Select and explain. 
A. Increasing the positive predictive value, B. Increasing the negative predictive value, C. Increasing the pretest odds, D. Increasing the specificity
B: Increasing the negative predictive value
Answer: B: Increasing the negative predictive value 
Explanation: In the given question, 2 tests - Impedence Plethysmography and leg scanning after injecting 125I fibrinogen are done together, for the diagnosis of Deep Vein Thrombosis.
Therefore these are two tests in done in parallel.