The ratio of the image distance to the object distance gives[[1]]of the lens.

The height of the picture and the object's distance can be used to define magnification. It is the proportion of object height to image height. In the mathematical formula, it is represented by the letter "m."
Let's start by defining magnifying. It is defined as the ratio of an image's height to an item's height, or the size of an image to the size of an object. It may also be described as the separation between the distance between an object and the lens from which an image is projected.
So. in a structured manner. One way to spell it is as

$\text{ Magnification }\left(\mathrm{m}\right)=\frac{\text{ Size of the Image }}{\text{ Size of the object }}$
$\Rightarrow m=\frac{h_2}{h_1}$
Or we use distance then-
$\Rightarrow \text{ magnification }\left(\mathrm{m}\right)=\frac{\text{ Image distance }}{\text{ object distance }}$
$\Rightarrow m=\frac{v}{u}$
Where, v-Image distance from the lens,
u - object distance from the lens.

Hence, the correct answer is magnification.