Question

which of the following is an invertebrate nekton species?

Explanation:

Nekton are organisms that can swim against water currents. Invertebrates lack a backbone. Seals and snakes are vertebrates. Jellyfish are invertebrates but are often considered plankton (drifters) rather than true nekton. Octopuses are invertebrates and are strong swimmers (nekton).

Answer:

The octopus (bottom - right image) is an invertebrate nekton species.