Explain yourself if you can and vote the one that you think is the closest, not for your favourite pair.

I think these two are because Sunny expresses genuine care for Taeyeon

second would be Jessica

Tiffany- Honestly I don't see them as close but more Tiffany almost dragging Sunny to be around her, is it just me?
hyoyeon- They dont seem close but that could be because Hyoyeon hangs out with her friends more than the group. She hasn't added Sunny on her instagram
Sooyoung- Not so close but I think it looks that way because of thier scedules
Yoona- Very close because Sunny invited Yoona on her show and too her to Roomates as a guest
Seohyun- not so close but i do think they care about one another
Yuri

i think her closest friends in SNSD are Taeyeon, Tiffany, Sooyoung and Yoona

I'd say Taeyeon and Yoona, since Taeyeon has always been considered as her best friend, and I think that Yoona's been really close with Sunny as of late.

Taeyeon!!

Taeyeon seems to be her closest friend in the band. They have cute moments, Sunny looks like she takes care of Taeyeon and vice Versa. Plus, the moments they have are really cute and seem meaningful. They are also one of my fave pairs!

She seems to really care for Taeyeon