The correct option is (a).
Explanation
The Indus River System is one of the world's largest river basins, traversing through China (Tibet), India, and Pakistan.
- Statement 1 is Correct: The river Indus rises in Tibet, near Lake Mansarowar. Specifically, it originates from a glacier near Bokhar Chu in the Kailash Mountain range at an altitude of 4,164 m. In Tibet, it is known as ‘Singi Khamban’ or Lion’s mouth.
- Statement 2 is Incorrect: The Indus enters India in the Union Territory of Ladakh, not Himachal Pradesh. It flows in a north-west direction between the Ladakh and Zaskar ranges, passing through Leh.
- Statement 3 is Incorrect: The Satluj, the Beas, the Ravi, the Chenab, and the Jhelum join together to form the Panjnad. These five rivers collectively enter the Indus river near Mithankot in Pakistan. The Indus flows southwards and eventually reaches the Arabian Sea east of Karachi. Karachi is located near the river's mouth, not the confluence point of its tributaries.
Key Takeaway: The Indus originates near Lake Mansarowar, enters India through Ladakh, receives the Panjnad (five rivers) near Mithankot, and discharges into the Arabian Sea near Karachi.