The following are the features associated with Cnidaria.
I. Radial symmetry
II. The presence of gastrovascular cavity
III. Animals are in either of the two forms -polyp and medusa or both.
IV. Alternation of generations in their history
WHich of the above are true of Metridium ?
A. I, II and IV
B. I and II
C. II and III
D. All of these
