Answer: B
Step-by-step explanation: The basic idea of a function is you put in some value for x and you get out something for y.
So for a table to be a function, each x term
needs to corresponds to exactly one y-term.
So yes, every x-value corresponds to exactly one y-value.
A common mistake would be to say that this is not a function
because the y-value of 3 repeats twice.
However, that's ok because you don't get
different y-values for the same x.
