The zone at the edge of a lake or ocean which is alternatively

The zone of lakes rich in planktons is

The zone of the ocean that does not receive sunlight is

The bottom zone in a lake is called

The bottom zone in a lake is called

What are the three zones of a deep lake on the basis of penetration of light.

Given figure represents the different zones of a lake or a pond. Identify the labelled parts X,Y and Z and select the correct statement.