The odd one out in this list is option 'B) Snake'.

Explanation:
1. Cow:
- Cows are domesticated animals and are commonly found in farms.
- They are herbivorous animals and feed on grass and other vegetation.
- Cows have four legs and are known for their milk production.

2. Snake:
- Snakes are reptiles and are known for their long, slender bodies.
- They do not possess legs and move by slithering on the ground.
- Snakes are carnivorous and feed on rodents, birds, and other small animals.
- Unlike cows, they are not domesticated animals and are usually found in the wild.

3. Elephant:
- Elephants are the largest land animals and are known for their size and strength.
- They have a trunk, which they use for various purposes like eating, drinking, and grabbing objects.
- Elephants are herbivorous and feed on a variety of plants, leaves, and fruits.
- They are known for their intelligence and sociability.

4. Tiger:
- Tigers are large carnivorous mammals and are known for their distinctive striped pattern.
- They are skilled hunters and feed primarily on other animals.
- Tigers are solitary animals and are found in various habitats, including forests and grasslands.
- They have sharp claws and powerful jaws, which they use for hunting and killing their prey.

Explanation:
- The odd one out in this list is 'Snake' because it differs from the other three options in several ways.
- Firstly, snakes are reptiles, while the other three options are mammals.
- Secondly, snakes do not possess legs and move by slithering, whereas cows, elephants, and tigers all have four legs.
- Thirdly, snakes are carnivorous, whereas cows and elephants are herbivorous and tigers are carnivorous mammals.
- Finally, snakes are not domesticated animals like cows and elephants, and they are usually found in the wild.

In conclusion, option 'B) Snake' is the odd one out as it differs from the other three options in terms of its classification, mode of movement, diet, and domestication status.