Multiple choice question what is the right answer

5. In order to detect the presence of a certain disease, a diagnostic test was given to a group composed of 55 people for whom the disease was present and 25 people who were disease-free. 60% of the test results were positive. 7 cases of false-positive results were obtained. What was the false-negative rate of this test ?

A) 0.75 B) 0.60 C) 0.48 D) 0.50 E) 0.25

(please show the steps of how you got to the answer)