History Suggests That the Most Dangerous Part of Nuclear Weapons

History suggests that the most dangerous part of nuclear weapons is:

A) how tempted countries are to use them in times of war.
B) the timing of their deployment at the end of wars.
C) the unevenness with which they have spread through the international system.
D) the frequency with which they have been used in the past.
E) their tendency to encourage the development of dangerous nuclear energy sources.