QUICK whoever gives correct answer will get brainliest please and thank you.

Answer:
A i think
Step-by-step explanation:
when theres function i like to think of vending machines
if you pick 5 you get soda
but in b if you pick 5 you get soda,candy,orange juice, etc.
so b is wrong
c is the same
if you pick 1 you get chips
but in c if you pick 1 you can also get chips, gummies, etc
i feel like D is wrong but im still thinking of how to explain it, ill edit my comment when i figure it out!
Edit:
D may look right, but pay very attention! theres some where 1 is equal to another number and where 2 also equals another number
(1, 2) and (1, 0)
(2, 3) and (2,1)