Answer: Euphotic or sunlit zone.
Explanation:
The top zone of the ocean is known as known as the sunlit zone or euphotic zone. Here the sunlight penetrates from the surface of the water.
This zone contains many organism which gets sunlight and perform photosynthesis by the help of sunlight.
The sunlight penetrates the water upto 660 feet and below this range the sunlight is hardly available so that it has only heterotropic organism there that feed on other organism for food.