Where are photosynthetic organisms least likely to be found?

Photosynthetic organisms are organisms that are capable of performing photosynthesis.These organisms are least found in the Benthic zone as it is the lowest level of a body of water. As sunlight cannot penetrate to the deeper parts, such organisms are least found here.As this region is not favourable for photosynthesis, such organisms cannot thrive here.

The answer would be c

Mg is used to measure mass