She’s the only person in history to be born with traits belonging to three magical races/species. This is why she’s called Tribrid. When they refer to her Tribrid status most people speak about her potential; what she will become. Though they never knew whether she’d still be a witch when she triggers her werewolf gene or whether she’d still be able to keep her magic when she becomes a vampire, they still see her as the rarest species because she has all three without needing external help.
In terms of what parts of her are active, all three are active, though she’s not a vampire yet she possesses vampire blood and it heals her.