Coastal districts of Tamil Nadu specialize in the cultivation of:

Cashew nuts
Coconut
Rice
All of the above

The correct answer is: d) All of the above

Cashew nuts, coconuts, and rice are all important crops in the coastal districts of Tamil Nadu. Cashew nuts are a major export crop, and coconuts are used in a variety of products, including coconut milk, coconut oil, and coconut water. Rice is the staple food of the region, and it is grown in both irrigated and rain-fed areas.

Cashew nuts are a major export crop in Tamil Nadu. The state is the second largest producer of cashew nuts in India, after Andhra Pradesh. Cashew nuts are grown in the coastal districts of Tamil Nadu, including Nagapattinam, Tiruvarur, Thanjavur, Pudukkottai, Ramanathapuram, and Sivaganga.

Coconuts are another important crop in Tamil Nadu. Coconuts are used in a variety of products, including coconut milk, coconut oil, and coconut water. Coconut milk is used in cooking, and it is also a popular drink. Coconut oil is used in cooking, and it is also used in cosmetics and soaps. Coconut water is a popular drink, and it is also used in sports drinks.

Rice is the staple food of the region, and it is grown in both irrigated and rain-fed areas. Rice is grown in the coastal districts of Tamil Nadu, including Nagapattinam, Tiruvarur, Thanjavur, Pudukkottai, Ramanathapuram, and Sivaganga.

The coastal districts of Tamil Nadu are a major agricultural region, and they produce a variety of crops, including cashew nuts, coconuts, and rice. These crops are important to the economy of the region, and they provide employment for a large number of people.