Select the Description That Most Completely Classifies the Given Variable

Select the description that most completely classifies the given variable
-A Prostate Specific Antigen (PSA) test is useful in detecting prostate cancer in men. A sample of blood is analyzed and the concentration of PSA is reported in nanograms per milliliter. Values less than 4.0 are considered normal and values over 10.0 indicate that further tests are needed. The best classification of the PSA variable is

A) Nominal
B) Qualitative, Ordinal
C) Quantitative, Continuous
D) Quantitative, Discrete