How do you unlock dry bowser and baby daisy on mario kart wii?

i know you need a star rank but what is a star rank and on what cup

How do you unlock dry bowser and baby daisy on mario kart wii?
Baby Daisy: Get a "One Star" rank or better in all 50cc cups.

Baby Luigi: Unlock eight Expert Staff Ghost Data in Time Trials mode.

Birdo: Play 16 different courses in Time Trials mode. Alternately, get 250 Wi-Fi wins.

Bowser Jr.: Get a "One Star" rank or better in all 100cc Retro Cups.

Daisy: Win the 150cc Special Cup.

Diddy Kong: Successfully complete all 50cc Retro Cups.

Dry Bones: Win the 100cc Leaf Cup.

Dry Bowser: Get a "One Star" rank or better in all 150cc Wii Cups.

Funky Kong: Unlock four Expert Staff Ghost Data in Time Trials mode.

King Boo: Win the 50cc Star Cup

Mii (Outfit A): Win the 100cc Special Cup.

Mii (Outfit B): Unlock all 32 Expert Staff Ghost Data in Time Trials mode.

Rosalina: Get a "One Star" rank or better in all Mirror Mode Retro Cups. Alternately, have a saved game file from Super Mario Galaxy and win 50 Grand Prix races.

Toadette: Play on all 32 courses in Time Trials mode. Alternately, get 1,000 Wi-Fi wins.