Which river forms the border between India and Nepal?

Explanation

The Kali River originates from Kalapani, near the Lipulekh Pass on the India–Tibet border. According to the Treaty of Sugauli, this river is regarded as the international boundary between India and Nepal. The Mahakali River, known as the Sharda River in India, is also called the Kali River. Hence, option (b) is the correct answer.