Why is the CMB in the microwave spectrum?

The cosmic microwave background (CMB) is thought to be leftover radiation from the Big Bang or the time when the universe began. As the theory goes, when the universe was born it underwent rapid inflation and expansion. ... Which means its radiation is most visible in the microwave part of the electromagnetic spectrum.

Explanation:

Hope this helps.

i think the answer would be b

radiation warms things up temp rises convection currents air circ windy weather