Correct Answer: Rohtang Pass

Solution : The correct answer is Rohtang Pass.

The Lahaul and Spiti valleys of Himachal Pradesh are connected to the Kullu valley through the Rohtang Pass. It is situated at 3,979 meters above sea level. On the Himalayan Eastern Pir Panjal Range, it is a lofty mountain pass. This pass is situated on the watershed that separates the Chenab and Beas basins. A highway tunnel beneath the Rohtang Pass is being constructed under the name Atal Tunnel, formerly known as Rohtang Tunnel.