The answer is C. Oyster.
The other four options are all animals that have a backbone. Oysters are invertebrates, which means they do not have a backbone.
Lizards are reptiles that have a long, slender body and a tail. They are found in many different parts of the world, and they come in a variety of sizes and colors.
Earthworms are invertebrates that live in soil. They are important for aerating the soil and helping to break down organic matter.
Snails are invertebrates that have a soft body that is protected by a hard shell. They are found in many different parts of the world, and they come in a variety of sizes and colors.
Spiders are arachnids that have eight legs and two body segments. They are found in many different parts of the world, and they come in a variety of sizes and colors.