Question 685197
The domain consists of all the unique values of x. So domain is -4, 0, 7
The range is all the unique values of y. so range is -6, -4, 0, 7

A function needs to pass the vertical line test. That means for every value in the domain the is one and only one vaue in the value.
Since a domain value of 7 is mapped to both 0 and -6, you fail the vertical line test. Thus it is NOT a function.

Answer : B