Answer:
Choice B is correct.
Step-by-step explanation:
We have given four relations.
We have to find the relation which is function.
A function is a relation that assigns each value of input exactly one output.
In the given relations, A relation in Choice B is a function because each input has exactly one output.
{(-1, 5), (-2, 6), (-3, 7)}
In other choices at least one value of input has two outputs.
For example, in choice C the input 11 has two outputs that is 9 and 5.
So B is correct.