Characters that are shared by members of both Cnidaria and Ctenophora are

a. They are sessile

b. Alternation of generations

c. Digestion is both extracellular and intracellular

d. Exhibit radial symmetry

e. Reproduction takes place only by sexual means

Characters shared by the members of both Cnidaria and Ctenophora are: digestion is both extracellular and intracellular; exhibit radial symmetry.

All ctenophores are free-swimming forms. Some cnidarians (e.g., sea anemones and corals) are sessile.

Alternation of generation (metagenesis) is exhibited by only cnidarians, but not ctenophores.

Reproduction takes place only by sexual means in ctenophores. Cnidarians reproduce both by asexual reproduction (e.g., budding in Hydra) and sexual reproduction.