Which of these is a common characteristic of cnidarians? a. they have four legs. b. they have tentacles with stinging cells. c. they live only in the oceans. d. they live only at the surface of the water

Hello there,

Which of these is a common characteristic of cnidarians?

All Cnidarians have tentacles with stinging cells in their tips which are used to capture and subdue prey.

Therefore, your answer would be
They have tentacles with stinging cells. (OptionB)