If you can order samples, then that would be outstanding, and you could give her a pretty little bowl of a dozen or more things to try.
Among those items to sample, I'd recommend:
~ Chanel No. 19 or Bel Respiro
~ Any of the Annick Goutal florals
~ A citrus scent (Eau d'Hadrien, O de Lancome)
~ And my favorite: Nanadebary Green