Given the fact "some hares live in fields", what is the answer to the question or completion "Sea hares are poisonous slugs, with tiny bunny-like tentacles, that float in water currents and ocean waves. They squirt a purple colored chemical that's sticky and smelly"

Choices: [I] to attract a mate. [II] to swim in deep waters. [III] to ward off predators. [IV] to color the water.
[III]