I think the answer is D.
Terrestrial can mean something living on Earth. (THEY ARE FOUND ONLY IN THE CENTER OF THE ISLAND) can back up that they live on Earth.
(THE MEANING OF TERRESTRIAL)
For animal that live on LAND it means they live predominantly or ENTIRELY on LAND.
For aquatic animals
They live predominantly or ENTIRELY in the OCEAN.
More information:
The term terrestrial is typically applied for species that live primarily on the ground, in contrast to arboreal species, which live primarily in trees.
There are other less common terms that apply to specific groups of terrestrial animals:
Saxicolous creatures are rock dwelling. Saxicolous is derived from the Latin word "saxum," meaning a rock.
Arenicolous creatures live in the sand.
Troglofauna predominantly live in caves.
Information found:
https://en.m.wikipedia.org/wiki/Terrestrial_animal