The change in focal length of an eye lens, to focus the image of objects at varying distances, is done by the action of
(a) pupil
(b) iris
(c) retina
(d) ciliary muscles
The change in focal length of an eye lens, to focus the image of objects at varying distances, is done by the action of
(a) pupil
(b) iris
(c) retina
(d) ciliary muscles