The correct option is B Photoreceptor cells
The rods and cones are the actual sites of transduction of light energy into neuronal signals. They are exceptionally specialised neurons, which have developed some structural features to carry out this task. The mechanism by which light energy is converted to neuronal signals is exactly the same in both rods and cones; the difference between the two types of receptor are in the visual pigments involved.
As a part of the retina, the bipolar cell exists between photoreceptors (rod cells and cone cells) and ganglion cells. They act, directly or indirectly, to transmit signals from the photoreceptors to the ganglion cells.