What are the causes of 'Myopia' ?

Explanation

Myopia, also known as short sightedness, occurs due to the lengthening of eye ball
(b) Nearby objects can be seen clearly but distant objects cannot be seen clearly
(c) The focal length of the eyelens is reduced or the distance between eye lens and retina increases.the retina
(d) Due to this, the image of distant objects are formed before the retina.
(ii) Draw a ray diagram, a ray is passing parallel to the optic axis of convex lens