Some species of jellyfish use jet propulsion to get around. True or False

The correct answer is "True".

Explanation:

Some species of jellyfish use a form of jet propulsion to swim and get around the sea. For instance, the jellyfish Polyorchis penicillatus contracts its subumbrellar swimming muscles to gain power, which it uses as mechanical energy to perform a jet cycle while swimming. Some studies in this regard have been performed, measuring even the amount of energy needed in the muscles for the jellyfish to swim.