Could you please explain what you mean by this sentence?
I just checked the exercise and it is quite strange.... What is shown is:
[An/The] actor and [an/the/] actress
It means one can get combinations like "An actor and the actress" (which is OK), but also "an actor and actress" (is this what you meant?) and "the actor and actress" which I find quite weird...
One of the other exercises has a very similar construction, but it suggests a/an for both of the professions. Is there significant difference, and if so, how can one tell?