The high-altitude Gurudongmar Lake is considered sacred by:

Hindus and Buddhists
Sikhs and Jains
Christians
Muslims

The correct answer is: a) Hindus and Buddhists.

Gurudongmar Lake is a high-altitude lake in the Himalayas, located in the East Sikkim district of Sikkim, India. It is the second highest lake in India, after Tso Moriri. The lake is considered sacred by both Hindus and Buddhists.

Hindus believe that the lake is the home of the goddess Lakshmi, the goddess of wealth and prosperity. They believe that bathing in the lake will bring them good luck and fortune.

Buddhists believe that the lake is the home of Guru Padmasambhava, also known as Guru Rinpoche, the founder of Tibetan Buddhism. They believe that the lake is a place of great spiritual power and that visiting the lake can help them to achieve enlightenment.

The lake is a popular tourist destination, and many people visit the lake each year to pray, meditate, and take in the stunning scenery.

Option b) Sikhs and Jains are incorrect because Gurudongmar Lake is not considered sacred by these religions.

Option c) Christians are incorrect because Gurudongmar Lake is not considered sacred by this religion.

Option d) Muslims are incorrect because Gurudongmar Lake is not considered sacred by this religion.