The correct answer is (b), Lipulekh Pass.
Lipulekh Pass is a high mountain pass in the Himalayas on the India-China border. It is located in the Pithoragarh district of Uttarakhand, India. The pass is at an elevation of 5,065 metres (16,620 ft) above sea level. It is the most important trade route between India and Tibet. The pass is open from May to November.
The other options are:
(a) Thangla Pass: This pass is located in the Ladakh region of Jammu and Kashmir, India. It is at an elevation of 5,360 metres (17,590 ft) above sea level. The pass is open from June to September.
(c) Barahoti Pass: This pass is located in the Pithoragarh district of Uttarakhand, India. It is at an elevation of 4,860 metres (16,000 ft) above sea level. The pass is open from May to November.
(d) Kingery-Bunger Pass: This pass is located in the Kinnaur district of Himachal Pradesh, India. It is at an elevation of 5,400 metres (17,700 ft) above sea level. The pass is open from June to September.