The correct answer is: All of the above.
The Sutlej, Beas, and Ravi are three major rivers in Himachal Pradesh that have several hydropower projects. The Sutlej River is the largest river in Himachal Pradesh, and it has several hydropower projects, including the Bhakra Dam, the Pong Dam, and the Nathpa Jhakri Dam. The Beas River is the second largest river in Himachal Pradesh, and it has several hydropower projects, including the Larji Dam, the Pandoh Dam, and the Chamera Dam. The Ravi River is the third largest river in Himachal Pradesh, and it has several hydropower projects, including the Salal Dam, the Ranjit Sagar Dam, and the Thein Dam.
These hydropower projects provide electricity to Himachal Pradesh and other parts of India. They also help to control flooding and improve irrigation. However, they have also had some negative environmental impacts, such as the displacement of people and the loss of biodiversity.