Answer the following question given this paragraph: 

The deep-water zone is dark so there is no photosynthesis. Most deep-water organisms are scavengers. They feed on dead organisms that fall to the bottom of the lake. Crabs and catfish are two of these types of organisms. Fungi and bacteria are decomposers that live in the deep zone.


Q: Why does photosynthesis not occur in the deep-water zone?

 Choices:

- it is cold

- it is pressurized

- it is stagnant

- it is dark

A:
it is dark
