The local police department gives a detective’s test. Everyone who takes the test must have been a police officer for at least 5 years. The people taking the exam are rated from top to bottom based on their scores on that test. Then, if any detective openings are available, they are filled on the basis of whoever has the highest score. Which of the following statements best describes this practice?

a. Tests like this are never legal in promotion decisions.
b. Tests like this are always legal in promotion decisions.
c. Tests like this are legal as long as they are not the sole factor used in determining promotion.
d. Tests like this are legal as long as the subject matter tested has some relationship to the job being applied for.