With which country did India sign the Indus Waters Treaty in 1960 with the help of the World Bank?

Pakistan

The correct answer is Option 4 - Pakistan

India and Pakistan also have had problems over the sharing of river waters. Until 1960, they were locked in a fierce argument over the use of the rivers of the Indus basin. Eventually, in 1960, with the help of the World Bank, India and Pakistan signed the Indus Waters Treaty which has survived to this day in spite of various military conflicts in which the two countries have been involved.
Jawaharlal Nehru for India and Ayub Khan for Pakistan were the signatories to the treaty.