Mountains, Hills, and Trekking Geography

Khyber Pass is located in the Spin Ghar mountains near the border between Pakistan and Afghanistan, connecting Peshawar with Kabul. It has historically been a vital trade route but is not within India's territory. The other options (Bomdila, Bara Lacha La, Shipkila) are all mountain passes within Indian territory.

The Aravalli Range is the oldest mountain system in India, dating back approximately 350 million years to the Proterozoic era. These ancient fold mountains run through Rajasthan, Haryana, Gujarat, and Delhi, and have been significantly eroded over geological time.

Kanchenjunga (8,586m) is the highest Himalayan peak within Indian territory, located in Sikkim on the border with Nepal. While Mount Everest (8,848m) is the world's highest peak, it lies on the Nepal-China border. Nanga Parbat and Nanda Devi are significant peaks but Kanchenjunga holds the distinction of being India's highest.

Nathula Pass is located in Sikkim, in the Himalayan mountains. It connects Sikkim with Tibet (China) and is one of the important border passes between India and China. It was a major trade route on the ancient Silk Road and has historical significance as part of the Indo-China border.

Nanda Devi (7816m) is the second-highest peak in India and is part of the Kumaon Himalayas in Uttarakhand. It gives the name to the Nanda Devi National Park.

The Nilgiri Hills in South India are called the 'Blue Mountains' due to the bluish hue of the kurinji flowers that bloom there. 'Roof of the world' refers to Tibet/Pamirs, and 'Tea treasures' is not a standard nickname for Nilgiris (though tea is grown there). The question has a typo ('know' should be 'known').

The approximate heights above mean sea level are: Darjeeling (~2,050m), Shimla/Simla (~2,276m), Kodaikanal (~2,133m), and Mahabaleshwar (~1,438m). In descending order (highest to lowest): Simla (2,276m) > Kodaikanal (2,133m) > Darjeeling (2,050m) > Mahabaleshwar (1,438m). Option B correctly places them in this descending sequence.

Arakan Yoma mountain range is the southern extension of the Himalayas, running through Myanmar (Burma) parallel to the coast. It forms the western boundary of the Irrawaddy River valley.

The Naga, Khasi, and Garo hills constitute the eastern extension of the Himalayan mountain system. While they are often classified as the Purvanchal Range specifically, they are geologically and geographically part of the broader Himalaya Range that runs across the northern Indian subcontinent.

Lhasa, the capital of Tibet (Autonomous Region of China), is situated at approximately 3,656 meters (11,990 ft) above sea level. This is significantly higher than Kathmandu (~1,400m), Thimphu (~2,300m), or Gartole, making Lhasa the city at the highest altitude among the options.

Mussoorie

Mount Kilimanjaro in Tanzania is Africa's highest peak at 5,895 meters (19,341 feet). It is a dormant volcano and the tallest free-standing mountain in the world.

Mount Kilimanjaro in Tanzania is the highest mountain in Africa at 5,895 meters. Mont Blanc is in Europe (Alps), Mt. Elbrus is in Europe/Russia (Caucasus), and McKinley (Denali) is in North America (Alaska).

Nilgiri Mountain Railway, started in 1908, was in news recently for announcing a shift from steam to diesel locomotives. Kalka Shimla Railway - 96 km long, Darjeeling Himalayan Railway - 86 km long and Nilgiri Mountain Railway - 46 km long

It lies between the valley of Kashmir and Kargil district.