Tamil Nadu is a significant producer of this plantation crop:

Coffee
Rubber
Cashew
Coconut

The correct answer is: c) Cashew

Tamil Nadu is a significant producer of cashew nuts. In 2020, the state produced 1.2 million tonnes of cashew nuts, making it the second largest producer in India after Andhra Pradesh. Cashew cultivation is a major source of employment in Tamil Nadu, with over 1 million people directly employed in the sector. The state also has a large number of cashew processing units, which export cashew nuts to various countries around the world.

Coffee is a major plantation crop in Kerala, Karnataka, and Andhra Pradesh. Rubber is a major plantation crop in Kerala, Tamil Nadu, and Karnataka. Coconut is a major plantation crop in Kerala, Tamil Nadu, and Andhra Pradesh.

Coffee is a brewed drink prepared from roasted coffee beans, the seeds of berries from certain Coffea species. The genus Coffea is native to tropical Africa (specifically having its origin in Ethiopia and Sudan) and Madagascar, Comoros, Mauritius, and Réunion in the Indian Ocean. Coffee plants are now cultivated in over 70 countries, primarily in the equatorial regions of the Americas, Southeast Asia, Indian subcontinent, and Africa. The two most commonly grown are C. arabica and C. robusta. Coffee has recently become a popular beverage in many parts of the world and is the second most traded commodity in the world after oil.

Rubber is an elastic polymer derived from the sap of several species of tropical plants. It is used in a wide variety of products, including tires, footwear, hoses, and gaskets. Rubber is produced by tapping rubber trees, which are native to Southeast Asia. The sap from the trees is collected and then processed to produce rubber.

Coconut is the fruit of the coconut palm, Cocos nucifera. It is a large, brown, fibrous fruit that grows in clusters on the tree. The coconut is a versatile fruit that can be eaten fresh, used in cooking, or processed to produce coconut milk, coconut oil, and coconut flour. Coconut is a popular food in many parts of the world, including Southeast Asia, India, and the Caribbean.