Please choose the correct ending to complete the given sentence: Sports and Fitness: [header] How to use color when fly fishing [title] Know how fishes' eyes are structured. [step] Human retinas contain two kinds of receptor cells, rods, and cones. Rods enable us to distinguish light from darkness and to see at lower levels of light, while cones function in brighter light and enable us to see colors.

Ending1: Most basically, you can only see how it is designed to operate. [substeps] Fabric assistants are the preferred option for people who do not want to hook fish frequently, have sharp or aggressively hooked rods, are trained for all shapes and sizes, and are able to hold lures. Ending2: The wide region in which fish' eyes form bases on the triangular structures of fish. In fact, the broad region of this globe displays the brightest light and lights most of all towns with a wide array of fish, such as sardines and salmon. Ending3: Fish eyes also contain both rods and cones, allowing them to see in color, with the proportion of rods to cones dependent on whether the fish inhabits relatively shallow or deep water. [title] Understand how water depth affects light penetration. Ending4: Fish are generally best sighted when they are exposed to light. It is in conjunction with human subjects, especially smaller changes in the fish's behavior, when they eat.

Answer format: ending1/ending2/ending3/ending4