<em><u>Photoreception is a type of reception of light detection that lead to vision and depends on specialized light-sensitive cells called photoreceptors, which are located in the eye.</u></em>
Photoreceptors are the cells in the retina that respond to light. There are 2 types of photoreceptors in the retina namely; rods and cones. The rods photoreceptors detect light and are located in the retina. Cone are photoreceptors that are located in the retina and detect color.
The answer is rr because if it were "Rr" it would be round. Dominant always exceeds the recessive. so if both traits were recessive, it would be recessive. so "rr" is your answer