Answer:

The odd one out in this group is option 'A' - Unicorn.

Explanation:

Unicorn is the odd one out in this group because it is a mythical creature, while the other options are all real animals.

Here is a detailed explanation for each option:

- Rhino: The rhino, also known as a rhinoceros, is a large mammal that is native to Africa and Asia. It is known for its distinctive horn(s) on its nose and its thick, armored skin. Rhinos are herbivorous animals, feeding on grasses, leaves, and other plant material.

- Fox: The fox is a small to medium-sized carnivorous mammal. There are many different species of foxes found around the world, including the red fox, Arctic fox, and gray fox. Foxes are known for their bushy tails and their ability to adapt to various habitats. They are omnivorous animals, eating both meat and plant material.

- Antelope: An antelope is a type of herbivorous mammal that is found primarily in Africa and parts of Asia. There are many different species of antelopes, including the impala, gazelle, and wildebeest. Antelopes are known for their slender build, long legs, and ability to run fast. They primarily feed on grass and other plant material.

- Unicorn: The unicorn is a legendary creature that is often depicted as a horse-like animal with a single horn on its forehead. It is a symbol of purity and grace in many mythologies and fairy tales. However, unicorns are not real animals and exist only in folklore and imagination.

Therefore, the odd one out in this group is the unicorn because it is the only option that is not a real animal.