The region in the eye where rods and cones are located is ___.

The correct option is A

Retina

The rods and cones are the photoreceptive cells of the retina, at the rear of the eye. The cones cells are responsible for colour vision, and are most dense in the central portion of the retina, an area called the fovea. The rod cells are incapable of distinguishing colour, but are more sensitive to light than the cones and so are responsible for vision in low-light situations. There are practically no rod cells in the central region, but an increasing number as you move out from the centre. In the very outer periphery of the retina, there are virtually no cone cells at all.