Which of the following is absent from the human eye?

Which of the following is not correct for rods?
$(I)$. Twilight vision is the function of the rods
$(II)$. It is responsible for daylight vision sometimes
$(III)$. The rods contain a protein called rhodopsin
$(IV)$. Rods are photoreceptor cells
Choose the correct option

Where is the $Macula$ $lutea$ located?

Which structure is covered by the iris?

What is the ciliary body?

The retina of a vertebrate eye contains ....