y as the function of x :
The y value of a point where a vertical line intersects a graph represents an output for that input x value. If we can draw any vertical line that intersects a graph more than once, then the graph does not define a function because that x value has more than one output.
In this graph :
for every value of x there is uniquew value of y! i.e
for x = 1, y = 1 and for x = -1 then y = 1
thus they statisfy the Many one relation
Hence the graph is the function of x.
B) In the given graph :
There are two lines which intersect at some point
So, they are the pair of linear equation
the given graph is not the function of x
C) The given graph :
these two pair parallel lines are parallel to x axis so, they have constant y value
thus, they are not the function of x
D) The given graph :
In this graphfor x = 1 y = 1 and -1
So, they show many to many relation hence it is not a function
Thus, the graph is not the function of x.
Answer : A)