The correct answer is: Only 3.
List I is a list of books about trekking in Himachal Pradesh, India. List II is a list of places in Himachal Pradesh.
The only pair that is correctly matched is Rupin pass – Valley of Shadows. Rupin pass is a mountain pass in the Himalayas, and the Valley of Shadows is a valley near the pass.
The other pairs are not correctly matched. On the footprints of Rohtang is a book about trekking in the Rohtang Pass, which is a different pass in the Himalayas. Choti Vilayat is a region in Himachal Pradesh, and Kunihar valley is a valley in the Choti Vilayat region.