2 is realistically going to be Yukari's reaction since I can't see Yukari getting flustered like in 3 though 4 may be her reaction as well if she had genuine feelings for anon.
Personally I want to see a flustered Yukari so 3.
Whatever, it's fine.
I will be using you for a while after this.Love... What an unusual human.... what are you saying?HAAAAAAAAAAAAH!?
L-l-l-l-LOVE!?... Saying it first is a bit... You cheater...Seriously... to think some lowly human would confess to me...Fu... Honestly. I was wondering what you wanted to say all of a sudden, but it was just love...