The most numerous livestock species in Tamil Nadu is:

Cattle
Goats
Poultry
Sheep

The correct answer is: Poultry.

Poultry is the most numerous livestock species in Tamil Nadu, accounting for over 60% of the state’s livestock population. The main types of poultry raised in Tamil Nadu are chicken, ducks, and geese. Poultry is raised for its meat, eggs, and feathers.

Cattle are the second most numerous livestock species in Tamil Nadu, accounting for about 20% of the state’s livestock population. Cattle are raised for their milk, meat, and draft power.

Goats are the third most numerous livestock species in Tamil Nadu, accounting for about 10% of the state’s livestock population. Goats are raised for their meat, milk, and hides.

Sheep are the least numerous livestock species in Tamil Nadu, accounting for about 5% of the state’s livestock population. Sheep are raised for their meat, wool, and hides.

Poultry is the most numerous livestock species in Tamil Nadu because it is a relatively low-cost and high-return enterprise. Poultry can be raised in small spaces, and they do not require a lot of land or water. Poultry also reproduce quickly, which means that farmers can quickly increase their flock size.

Cattle are the second most numerous livestock species in Tamil Nadu because they are a versatile animal that can be used for a variety of purposes. Cattle can be used for their milk, meat, and draft power. They can also be used to produce manure, which can be used as a fertilizer.

Goats are the third most numerous livestock species in Tamil Nadu because they are a hardy animal that can survive in a variety of climates. Goats can also be raised on marginal land that is not suitable for other types of livestock.

Sheep are the least numerous livestock species in Tamil Nadu because they are a relatively high-cost and low-return enterprise. Sheep require a lot of land and water, and they do not reproduce as quickly as poultry or goats.