Question

within the phylum cnidaria, which of the following describes the polyp form?
a moving, umbrella shaped cnidarian that buries itself deep into the sand
a cone shaped cnidarian with tentacles facing downward
cylindrical shaped cnidarian with tentacles facing upward

Explanation:

Cnidarians have two main body forms: polyp and medusa. The polyp form is typically cylindrical, attached to a substrate, and has tentacles facing upward to catch prey. The description "a moving, umbrella - shaped cnidarian" describes the medusa form. A cone - shaped cnidarian with tentacles facing downward is not the typical polyp description.

Answer:

cylindrical shaped cnidarian with tentacles facing upward