How do you unlock daisy in Mario Kart ds?

Hey, I'll give you a bonus! To unlock Daisy, win gold in all Retro cups! She is totally awesome! And to unlock Dry Bones, win gold on all Nitro cups! He's Yoshi in his bones, FYI. And to unlock Waluigi, win gold in all 100cc Retro cups! He is really weird! And to unlock a new kart for all your characters, win gold in all 100cc cups! Good luck!