The correct answer is D. Gandak Project.
The Gandak Project is a joint irrigation project of the States of Bihar and Uttar Pradesh. It is a multi-purpose project that includes irrigation, flood control, and power generation. The project was started in 1954 and was completed in 1969.
The Gandak Project has a total installed capacity of 1,000 MW. It irrigates an area of 2.2 million hectares in Bihar and Uttar Pradesh. The project also provides flood control to an area of 1.5 million hectares.
The Gandak Project is a major source of irrigation and flood control for the States of Bihar and Uttar Pradesh. It has also helped to improve the socio-economic conditions of the people living in the project area.
The other options are incorrect because they are not joint irrigation projects of the States of Bihar and Uttar Pradesh.
- Option A: The Darnodar Valley Project is a joint irrigation project of the States of Gujarat and Maharashtra.
- Option B: The Kosi Project is a joint irrigation project of the States of Bihar and Nepal.
- Option C: The Son Barrage Project is a joint irrigation project of the States of Madhya Pradesh and Uttar Pradesh.