Answer:
Option (D).
Step-by-step explanation:
If the graph of a relation has two output values for a single input value, relation will not be considered to be a function.
Option (A).
For the input values of x = -1, there are two output values, y = -1, 1.
Therefore, given relation is not a function.
Option (B).
Since, all the parabolas don't represent a function, given parabola in the graph is not a function.
Option (C).
Not a function. It's a relation.
Option (D).
Line plotted in the graph has a distinct output value for every input value.
Therefore, the given graph represents a linear function.
