Which of the following is not a function?

a. ( Manila,Philippines ) , ( Tokyo,Japan ) , ( Paris,France )
b. ( Grade 7,Glenda ) , ( Grade 8, Mark ) , ( Grade 8,Helen )
c. ( G7,green ) , ( G8,yellow ) , ( G9, red )
d. ( Pangasinan,Region I ) , (Cagayan,Region II ) , ( Bulacan,Region III )

Pahelp po,,kailangan na kailangan lng po talaga plss..

Ma-mark ko po yung sasagot,,salamat rin po..