Giraffes don't go to work

It’s at the base of the neck. It would be really weird if humans pushed their ties all the way up

Considering we as humans wear our ties at that base of our neck, I'd have to say option 2. However, as giraffes have to pump blood up a longer neck, wearing a potentially suffocating tie wouldn't be in the giraffe's best interests. There's also no feasible way for a giraffe to put on a tie as it doesn't have the capability to perform the required motions to hold or tie a tie. Although it could ask a human or other dexterous animals to do it by using pictures drawn with a stick in its mouth, choosing this option would require the giraffe being a good artist or the human/animal being good at Pictionary. Alternately the giraffe could wear a clip-on tie. But that's just my opinion and you might want to find a more expert opinion. Giraffing the wrong guy here.

Top for more formal. Bottom for slacking off