Answer: A. A fluid or air-filled space between the digestive tract and the outer body wall. - Coelom
B. Completely lacks a body cavity between the digestive cavity and outer body wall. - Acoelomate
C. Has a body cavity lined by tissue derived from the mesoderm and by tissue derived from the endoderm. - Coelomate
D. Has a body cavity completely lined by tissue from the mesoderm. - Pseudocoelomate
E. Germ Layer- Coelomate
Explanation:
Coelom is a fluid filled body cavity which stores food, blood like fluid in it in some animals.
Those organisms which do not possess the body cavity or coelom they are called as acoelomate. Example, Platyhelminths
Those animals which have a body cavity derive from the germinal layers ectoderm, endoderm, and mesoderm are coelomate. Example, Annelids
Those animals which have scattered pouches which are not lined by all germinal layers instead one mesoderm will not be able to form coelom. These are called as pseudocoelomate. For example, Nematodes.
