black ink in water causes animals to have difficulty seeing & a predator is a kind of animal ->  black ink in water causes predators to have difficulty seeing  black ink in water causes predators to have difficulty seeing & octopuses release black ink into water ->  octopuses releasing ink into the water causes predators to have difficulty seeing the octopus  octopuses releasing ink into the water causes predators to have difficulty seeing the octopus & hiding means ability to be seen decreases for camouflage -> ink is used for hiding from predators by octopuses