The correct answer is skeletal development resulting in the movement of amphibians onto land and possibly evolved from lobe-finned fishes.
The initial lobe-finned fishes are bony fish with lobed, fleshy, paired fins that are connected with the body by a solitary bone. The fins of the lobe-finned fishes vary from those of all other fish in that each is borne on a lobe like, fleshy, scaly stalk protruding from the body.
This skeletal development will show that the species first developed in water and then gradually move onto the land and ultimately developed as species of land.
A cell wall, because animal cells have a cell membrane, ribosomes are used to reproduce some proteins same goes for mitochondrias.
Lava rock contain a fossil
Cord? Or maybe vein. But I strongly believe it’s cord
