What is mutual assured destruction $($MAD$)?$

Select one:

A$.$ the inhibition of a first strike nuclear attack by an effective retaliatory or second$-$strike capability

B$.$ the strategic approach to enhance deterrence by constructing "dummy" nuclear silos to undermine Soviet confidence in their targeting decisions

C$.$ the strategic approach to concentrate the placement of missiles without efforts to conceal their whereabouts in order to preserve the capacity to retaliate

D$.$ the logic that assumes the certainty of a nuclear retaliation would prevent governments from launching such an attack in the first place