Respuesta :
The phrase that reflects the idea that the superpowers would avoid nuclear war due to fear of mutual annihilation is C. Mutually assured destruction.
The détente was a period of time during the Cold War characterized by B. A relaxing of tension
What is the Cold War?
This refers to a period of conflict between the United States and the USSR over the spread of communism.
We can also note that the phrase that reflects the idea that the superpowers would avoid nuclear war due to fear of mutual annihilation is mutually assured destruction.
Read more about Cold War here:
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