Read this line from the prologue of Romeo and Juliet.

A pair of star-cross'd lovers take their life;

Having heard this line in the prologue the audience can

A. Understand why Romeo and Juliet kill themselves in the play

B. Know which characters act as enemies of Romeo and Juliet

C. Predict that Romeo and Juliet do not survive at the end of the play

D. Wonder what finally happened to the characters of Romeo and Juliet

I would say C, Predict that they do not survive at the end of the play, because the specific line doesn't reveal why nor does it reveal the enemies. It reveals what happens to Romeo and Juliet so the answer can't be D.

C. Predict that Romeo and Juliet do not survive at the end of the play

The line specifically tells you that a pair lovers commit suicide. They do not survive at the end of the play. An audience, who knows nothing about the play, does not know that the lovers are Romeo and Juliet until a bit later since the prologue does not mention their names. However, the audience does know that it is the children of the feuding families when it says "from forth the fatal loins of these two foes".