If Two States Possess Nuclear Weapons,but Neither Side Possesses Second-Strike

If two states possess nuclear weapons,but neither side possesses second-strike capability,what effect does this have on relations between the two countries?

A) The countries should be more capable of resolving their differences since they will now have the interests of nuclear powers,distinct from those countries that rely on conventional weapons.
B) The two states are more likely to be bitter rivals,since nuclear states are typically irrational.
C) The lack of second-strike capability makes first strikes more rewarding and may make nuclear war more likely.
D) It will likely not have an effect,as conventional forces can readily serve as second-strike forces to any nuclear attack.