The correct answer is (c) Mandakini.
The Mandakini is a river in the Garhwal Himalayas of Uttarakhand, India. It is a tributary of the Alaknanda River, which in turn is a tributary of the Ganges River. The Mandakini originates in the Kedarnath Glacier and flows through the Kedarnath Valley before joining the Alaknanda River at Karanprayag. The Mandakini is a sacred river for Hindus and is a popular pilgrimage destination.
The Bhagirathi is another tributary of the Alaknanda River. It originates in the Garhwal Himalayas and flows through the Garhwal Valley before joining the Alaknanda River at Vishnuprayag. The Bhagirathi is also a sacred river for Hindus and is a popular pilgrimage destination.
The Pinder is a tributary of the Alaknanda River. It originates in the Garhwal Himalayas and flows through the Garhwal Valley before joining the Alaknanda River at Rudraprayag. The Pinder is not a sacred river and is not a popular pilgrimage destination.
The Dhauli Ganga is a tributary of the Alaknanda River. It originates in the Garhwal Himalayas and flows through the Garhwal Valley before joining the Alaknanda River at Devprayag. The Dhauli Ganga is not a sacred river and is not a popular pilgrimage destination.