The cold war was mainly an ideological war of ideas but it had occasional military flare ups name two times the cold war became hot

The ever hotest  time in the cold war was during the cuban crisis.   A spy usa pilot in the sky saw a soviet missile being assembled in Cuba.

There was threat of nuclear reatliation as a result.

The 1979 NORAD Computer Glitch
 the two super powers came again to the brink of nuclear war in 1979 after a false nuclear alert.  Usa assembled its fighter jet, including the presidential dooms day fighter for retaliation.

Ithink it's c selection but i don't really know.