Answer:
Picture number 3 is the answer
Step-by-step explanation:
A function is a relation in which each element in the domain is paired with exactly one element in the range not 2.
Picture number one has a range left with no domain so it's not a function
Picture number 2 is showing an element in the domain which paired 2 elements in the range so it's not a function
Picture 3 is correct because each element in the domain macthes one element in the range.
Picture 4 is wrong because it's showing elements in the domain that matches 2 elements in the range. Hope it makes sense.
