What Was the Assumption of Behind "Mutual Assured Destruction

Multiple Choice

What was the assumption of behind "mutual assured destruction"?

A) In a U.S.-Soviet crisis Washington would have to launch a nuclear strike first to avoid a Soviet second strike.
B) Only mutual vulnerability to nuclear attack could prevent nuclear war.
C) A full-scale nuclear exchange would produce nuclear "winter".
D) The construction of effective U.S. and Soviet anti-missile defenses would allow both to escape destruction in a nuclear war.