In the following question, out of the given four alternatives which best expresses the meaning of the Idiom/Phrase.

A blast from the past 

Something powerfully nostalgic 

The idiom "a blast from the past" refers to something that is from the past and that evokes nostalgic feelings. It is often used to describe something that is old, but that is still remembered fondly.

For example, you might say "That song is a blast from the past. I used to listen to it all the time when I was a kid." or "Meeting my old high school friends was a blast from the past. We had so much fun catching up."