Introduction:
Siachen Glacier is one of the most strategically important and highest battlefields in the world. It is located in the Karakoram Range of the Himalayas and is currently under the control of India. It holds immense military significance as it forms the northernmost point of the Indian subcontinent.

Explanation:
Siachen Glacier is part of the Karakoram Range, which is one of the major mountain ranges in the world. Here is a detailed explanation of why option 'A' - Karakoram Range is the correct answer:

1. Karakoram Range:
The Karakoram Range is a mountain range that spans across the borders of India, Pakistan, and China. It is a part of the greater Himalayan mountain system and is known for its massive glaciers, including the Siachen Glacier. The Karakoram Range is home to some of the highest peaks in the world, such as K2, the second-highest peak after Mount Everest.

2. Siachen Glacier:
Siachen Glacier is located in the eastern Karakoram Range in the Himalayas. It is the longest glacier in the Karakoram Range and the second-longest non-polar glacier in the world. The glacier stretches for about 76 kilometers and is spread over an area of around 2,500 square kilometers.

3. Importance and Conflict:
Siachen Glacier holds immense strategic importance due to its location. It is situated at the northernmost point of the Line of Control (LOC) between India and Pakistan. The region has witnessed military conflicts between the two nations since 1984. Both countries maintain military presence in the region, despite the harsh weather conditions and treacherous terrain.

4. Climate and Challenges:
The Siachen Glacier is known for its extreme climate, with temperatures dropping as low as -50 degrees Celsius. The area receives heavy snowfall and experiences avalanches, making it a challenging environment for military operations. The soldiers stationed in the region face severe physical hardships and risks associated with high altitude warfare.

Conclusion:
In conclusion, Siachen Glacier is part of the Karakoram Range, which is a major mountain range in the Himalayas. The glacier's strategic location, extreme climate, and military conflicts make it a significant and challenging battleground.

Option A is correct