How do I check if one of these audiosources is playing before playing the other?

if (collision.transform.tag == "Motley") { audioSourceD.Play(); }

     if (collision.transform.tag == "Caspro")
     {
         audioSourceE.Play();
     }

I have these 2 different audiosources playing when my player collides with 2 different game objects. So currently it is possible to play one when the other one is already playing and it sounds like cacophony. What I want to happen is before either one plays it checks if the other is already playing and if so it doesnt play.