The correct answer is Japan.
The Swan River Integrated Watershed Management Project is a joint project between the Government of India and the Government of Japan. The project aims to improve the management of the Swan River watershed in Una district of Himachal Pradesh. The project will focus on improving water quality, reducing soil erosion, and increasing agricultural productivity.
The project is being implemented by the Japan International Cooperation Agency (JICA). JICA is a Japanese government agency that provides international development assistance. JICA has a long history of working in India, and has implemented a number of successful projects in the country.
The Swan River Integrated Watershed Management Project is a significant project that will have a positive impact on the lives of people in Una district. The project will improve the quality of life for people in the district by providing them with access to clean water, reducing soil erosion, and increasing agricultural productivity.
The project is also expected to have a positive impact on the environment. The project will help to reduce pollution in the Swan River, and will help to protect the watershed from soil erosion.
The Swan River Integrated Watershed Management Project is a valuable partnership between the Government of India and the Government of Japan. The project will have a positive impact on the lives of people in Una district, and will help to protect the environment.
The other options are incorrect because they are not countries that are assisting in the Swan River Integrated Watershed Management Project.