Answer : 4. "पाकिस्तान"
Explanation :

The Indus River (locally called Sindhu) is one of the longest rivers in Asia, originating in the Tibetan Plateau in the vicinity of Lake Manasarovar, the river runs a course through Ladakh towards the Gilgit-Baltistan region Hindukush ranges, and then flows in a southerly direction along the entire length of Pakistan