Answer:
This is not a function.
Step-by-step explanation:
A function by definition will map one element of the domain to one element of the range. In this example, we would need one element of A to match one element of B for all elements of A.
Note, there are two elements in set A that map to one element in set B, while one element in set B has no mapping from any element in set A.
Cheers.
