Short-sightedness or myopic vision is corrected by wearing:

Which of the following statements are correct for the iris?
$(I)$. The ciliary body extends forward to form the iris.
$(II)$. It is a pigmented and opaque structure.
$(III)$. It is the visible coloured portion of the eye.
Choose the correct option.

What is the correct sequence of the parts of the eye that light rays pass through to reach the retina?

In mammals,which cells are responsible for colour detection in the retina?

In the retina of the human eye,the cones are concentrated more at the

The visual acuity is the greatest at