What do playwrights write to them tell their stories?

a. dialogue

b. editorials

c. advertisements

d. narration

It could be A or D,a dialogue is between character's however you could also have an narrator that stands of to the side that gives an over view of what is happening on the stage a few examples of this include the play the laramie project, stories in the dark 

however if the question is to be one or the other it is more likely A because it is more common in a play then narrations

The best and most correct answer among the choices provided by the question is A.dialogue .

Dialogue helps playwrights write to tell their stories.

Hope my answer would be a great help for you.    
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