The correct answer is option 'D', Triticale.

Explanation:
Man-made cereals are hybrid crops that are created by crossbreeding different species of plants. Triticale is one such man-made cereal that is produced by crossing wheat (Triticum) with rye (Secale cereale).

Triticum:
- Triticum is the scientific name for wheat, which is a widely cultivated cereal grain.
- It is a natural cereal that has been grown for thousands of years and is a staple food for many cultures around the world.

Hordeum:
- Hordeum is the scientific name for barley, which is another widely cultivated cereal grain.
- Barley is a natural cereal that has been cultivated for thousands of years and is used for various purposes such as brewing, animal feed, and food.

Eleusine:
- Eleusine is the scientific name for finger millet, which is a natural cereal grain.
- Finger millet is grown in Africa and Asia and is known for its nutritional value and resilience to harsh growing conditions.

Triticale:
- Triticale is a man-made cereal that was first produced in the late 19th century.
- It is a hybrid crop created by crossing wheat and rye, combining the desirable traits of both species.
- Triticale has higher yields and better disease resistance compared to its parent plants.
- It is primarily used as livestock feed but can also be used for human consumption, especially in bread and other baked goods.

In conclusion, Triticale is the man-made cereal among the given options. It is a hybrid crop created by crossing wheat (Triticum) and rye (Secale cereale), combining the desirable traits of both species.