The collection of rod and cone receptors that funnel signals to a particular visual cell in the retina make up that cell's: A. blind spot. B. optic disk. C. opponent process field. D. receptive field.

First, let's define each term to understand their roles in the retina and the vision process: A. Blind spot: The point on the retina where the optic nerve exits the eye, creating a small area where no photoreceptor cells exist, and, thus, no vision is possible. B. Optic disk: The location where the optic nerve and blood vessels exit the eye, corresponding to the blind spot. C. Opponent process field: A theory explaining color vision based on the idea that our visual system processes colors as opposing pairs (red-green, blue-yellow, and white-black). This term doesn't directly relate to the structure of the retina and photoreceptor cells. D. Receptive field: The area of the retina to which a specific visual cell (such as a rod or cone) responds, receiving and funneling signals from multiple photoreceptor cells to a single visual cell.

Now that we've defined each term and its relevancy to the retina and vision process, we can analyze which term best fits the exercise prompt: the collection of rod and cone receptors that funnel signals to a particular visual cell in the retina. Based on the definitions, the correct term is: D. Receptive field