Behati is not big enough for the 20th anniversary, she is not enough known, except if she gets it because Maroon 5 will perform, that is another thing. I vote for Candice because it is anniversary and because out of all angles I think she has done the most work for VS, they put her in everything when they need something to sell, and she is their main face and queen for years now(alongside Adriana, but Adriana is fading). Adriana and Candice are Victoria Secret, without them whole brand is not special anymore.