Answer : 4. "Ghaggar River"
Explanation :

1. Ghaggar-Hakra River is a seasonal river flowing during the rainy season in India and Pakistan.

2. It is known as the Ghaggar River before the Ottu Veer Dam in Haryana and the Hakra River beyond it.

3. According to some scholars, this is the only surviving form of the great Saraswati river that flowed in ancient times.

4. The Ghaggar originates near Shimla in the Shivalik mountains of Himachal Pradesh, during the monsoon rains from Kalka to Ambala in Haryana and Punjab.

5. From here it enters Rajasthan where in a basin it forms Talwara Lake in its course of flow.