Which line best adds to a threatening mood in act ii, scene ii of romeo and juliet?

a. what’s montague? it is nor hand, nor foot,
b. call me but love, and i’ll be new baptiz’d;
c. thou know’st the mask of night is on my face,
d. if they do see thee they will murder thee.

The answer is:

D.If they do see thee they will murder thee.

In Elizabethian thee was used to speak of you*, "this would be translated to if they do see you, they will murder you", Juliet speaks to Romeo about the danger of being there with her. And he replies by saying that "one angry look from you would be worse than twenty of your relatives with swords."-

That´s why that line ads to the threatening mood.

might need to ask questions people no or have read somthing about.