Answer:
a. Tetrapods are no longer tied to the water for reproduction.
Explanation:
Amniota Egg.
It is an egg that is isolated and protected from the environment during the period of its development by a series of extraembryonic membranes and, often, a more or less impermeable shell; Amniotic eggs of birds and many reptiles are completely autonomous and only require oxygen from the outside .
The appearance of the amniota egg in a group of tetrapods made possible the most complete conquest of terrestrial habitats. This group of tetrapods called amniots is currently represented by reptiles, birds and mammals; Its origin dates back to the Carboniferous.
The Amniota egg, in it, the embryo generates three envelopes, Corion, Alantoides and Amnios, which make up an aqueous medium that allowed it to breathe and feed during its development. They also have a calcareous envelope that prevents desiccation, without preventing the exchange of gases and then allowing their development in a terrestrial environment.