The animal without skull is
Acrania
The correct option is A:
Explanation for the correct option:
Explanation for the incorrect options:
Option B:
Option C:
In many avian species or birds, the naked spaces or skin between the feathered areas is called apteria.
Option D:
The absence of a coelom and a body cavity is called acoelomate.
Final answer: The absence of a fetal skull in animal with freely uncover brain tissue to amniotic fluid is called acrania.