The right answer is Lichen.
In ecology, a pioneer species is one of the first forms of life that colonize or recolonize a given ecological area.
Lichens are composite organisms resulting from a symbiosis between at least one heterotrophic fungus called mycobionte, representing 90% of all, and microscopic cells with chlorophyll (green algae or cyanobacteria autotrophic for carbon) called "photobionts" .
I think the answer is the last option or D) but i think i am wrong
Well a mutation is like a change in the DNA and so if there was a mutation in the antártica fish, something in their genes would change. If that mutation has a positive effect on it, then that mutation would be passed down to the generations of fish, helping that fish with its survival or something
The ocean basins are grooved and ridged