Indus
Explanation
The drainage system of the Indian subcontinent is geographically divided based on the origin and flow of rivers. The Ladakh region, situated in the Trans-Himalayas, is primarily drained by the Indus river system.
- Ganga is incorrect: The Ganga originates from the Gangotri Glacier in Uttarakhand. It flows through the states of Uttarakhand, Uttar Pradesh, Bihar, and West Bengal before entering Bangladesh. It does not flow through the Ladakh region.
- Indus is correct: The Indus River originates near Lake Mansarovar in Tibet. It enters India in the Union Territory of Ladakh and flows in a north-westerly direction between the Ladakh and Zanskar mountain ranges. It is the most significant river flowing through this high-altitude desert region.
- Brahmaputra is incorrect: The Brahmaputra originates near Lake Mansarovar in Tibet (where it is known as the Yarlung Tsangpo). It flows eastward, parallel to the Himalayas, and enters India through Arunachal Pradesh. It does not traverse Ladakh.
- Yamuna is incorrect: The Yamuna originates from the Yamunotri Glacier in Uttarakhand. It flows through Uttarakhand, Haryana, Delhi, and Uttar Pradesh to merge with the Ganga at Prayagraj. It does not flow through Ladakh.
Key Takeaway: The Indus River is the primary drainage system of the Trans-Himalayan region in India, flowing specifically through the Union Territory of Ladakh.