The epipelagic zone is also referred to as which of the following?

• A. Sunlight zone
• B. Twilight zone
• C. Deep zone
• D. Middle zone

Answer: (A)

The epipelagic zone is the sunlit portion of the ocean where enough light reaches for photosynthesis, so it’s commonly called the sunlight zone. This is the uppermost layer, roughly down to about 200 meters in clear water, where light supports phytoplankton—the base of most marine food webs.

That’s why the term “sunlight zone” fits best. The twilight zone refers to the mesopelagic zone, where light is faint and not enough for photosynthesis. The deep zone describes deeper, lightless layers such as the bathypelagic and beyond. A “middle zone” isn’t a standard term used for ocean layers.