Answer:
Dilation : The meaning of Dilation is that by taking a fixed center and certain real number we can either enlarge an image or reduce it's size without actually changing it's shape. it totally depends on amount by which we are dilating if it is a real number greater than 1 the size of image increases otherwise shrinks means smaller in size.
The original image is called Pre-image and after dilation that changed image is called image.
So, we can say that Dilation is a function because for each different scale factor or different real number we get different images.
So, Out of all the four options given first looks completely true about Dilation.
i.e A dilation is a function because every point on the pre-image corresponds to exactly one point on the image.
