With Regard to Nuclear Weapons, Which of the Following Statements

With regard to nuclear weapons, which of the following statements is incorrect?

A) Both the United States and Russia have significant stockpiles of nuclear warheads over and above the 1,550 each has deployed under the START Treaty.
B) The countries that now possess nuclear weapons include the United States, Russia, China, India, Pakistan, the United Kingdom, and France, and North Korea has tested nuclear warheads.
C) Thanks to the START and SORT treaties, not only has the danger of long-range strategic nuclear weapons been dramatically reduced, but there have also been significant reductions in short-range tactical nuclear weapons as well as stockpiles of fissionable material.
D) Even with the reductions in nuclear weapons under SORT and START, all-out nuclear war could destroy a good share of civilization as we know it.