4. An investigator develops a biochemical test for depression, which he evaluates in a series of 100 persons who are also assessed clinically for depression. The results of the study are: Test Findings Clinical Depression Present Negative Positive Which of the following ratios measures the false positive? 30 12 (a) $12 /(12+35)$ (b) $30 /(12+30) $ (c) $35 /(35+25)$ (d) $25 /(30+25)$ (c) none of the above SP.AS. 1185