This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Vitreous and retina, Subject name: Ophthalmology
Which retinal layer is most radioresistant- 
Select and explain. 
A. RPE, B. Layer of rods and cones, C. Bipolar cell layer, D. Ganglion cell layer
B: Layer of rods and cones
Answer: B: Layer of rods and cones 
Explanation: Rods and cones are the end organs of vision and are also known as photoreceptors. Layer of rods and cones containsonly the outer segments of photoreceptor cells arranged in a palisade manner. There are about 120 millions rods and 6.5 millions cones. Rods contain a photosensitive substance visual purple (rhodopsin) and subserve the peripheral vision and vision of low illumination (scotopic vision). Cones also contain a photosensitive substance and are primarily responsible for highly discriminatory central vision (photopic vision) and colour vision. Ref:comprehensive ophthalamology A k khurana 4/E pageno:250 Layer of rods and cones.