If the Threatened Use of Nuclear Weapons in War Is

If the threatened use of nuclear weapons in war is credible,what effect does this have for the bargaining model of war in a conflict between two nuclear states?

A) It increases the potential benefits for a nuclear state.
B) It increases the potential costs asymmetrically for the two states.
C) Third parties should be more likely to intervene to prevent the conflict.
D) War will be more likely,as states will want to make sure they attack first.
E) It expands the acceptable bargain range for both parties.