The Local Police Department Gives a Detective Test

The local police department gives a detective test.Everyone who takes the test must have been a police officer for at least five years.The people taking the exam are rated from highest to lowest based on their test scores.If a detective position becomes available,it is filled on the basis of who 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 the subject matter tested has some legitimate relationship to the job in question.
D) Tests like this are legal, as long as they are not the sole factor used in determining promotion.
E) Tests like this are legal, as long as they are the sole factor used in determining promotion.