The function becomes even when f(-x) = f(x)
So, if f is even function and y = f(x)
∴ y = f(-x)
∴ (x,y) and (-x,y) on the same graph
or we can say (-x,y) is an image for (x,y)
So, the rule of transformation becomes (x,y) ⇒⇒⇒ (-x,y)
Which is the same rule of reflection over the y-axis.
∴ The correct choice is the second option
