An article in a magazine states that the people who work in uranium mines are likely to suffer from diseases. Which of these is the most reliable method to verify the information provided by the magazine?

a. ask scientists to analyze the effects of radiation on humans
b. ask geologists to test the harmful radiations emitted by uranium
c. ask doctors to treat patients who have never worked in uranium mines
d. ask uranium mining companies to check the radiations emitted in their mines