Answer:
Letter D
Step-by-step explanation:
Benthic organisms are identified as species that live in relation to the bottom (substrate), either to attach to it or to drill, dig and/or walk on a surface. The substrate can be consolidated (rocks, wood, wharf, etc.) or unconsolidated (sand, mud, etc.). Benthic organisms are composed of macroalgae, microalgae and aquatic plants (phytobenthos); animals and many protists (zoobenthos).
So, Tuna isn't a benthic organism and the right answer is Letter D.