The primary source of irrigation in Nagaland is:

The primary source of irrigation in Nagaland is rainwater. This is because Nagaland is a mountainous state with a high rainfall. The average annual rainfall in Nagaland is about 2,500 mm. This rainfall is used to irrigate crops such as rice, maize, and vegetables.

Canals are not a major source of irrigation in Nagaland because the state does not have a well-developed canal system. Tube wells are also not a major source of irrigation in Nagaland because the state does not have a lot of groundwater. Drip irrigation is a relatively new technology in Nagaland and is not yet widely used.

Here is a brief explanation of each option:

• Rainwater: Rainwater is the primary source of irrigation in Nagaland. It is collected in tanks and reservoirs and then used to irrigate crops.
• Canals: Canals are artificial waterways that are used to transport water from rivers or lakes to fields. They are not a major source of irrigation in Nagaland because the state does not have a well-developed canal system.
• Tube wells: Tube wells are vertical wells that are drilled to extract groundwater. They are not a major source of irrigation in Nagaland because the state does not have a lot of groundwater.
• Drip irrigation: Drip irrigation is a method of irrigation that delivers water directly to the roots of plants. It is a relatively new technology in Nagaland and is not yet widely used.