What is a conjunction?
A conjunction is a part of speech that is used to connect words, phrases, clauses, or sentences. Conjunctions are considered to be invariable grammar particle, and they may or may not stand between items they conjoin.
It is the third one: I felt bliss when I found out the dog had her puppies.
It cannot be the first one because bliss is not a product that you can use.
It is not the second one because bliss is not something you can touch.
And it is not the last one because bliss is not a place to which you can go.