Who among the following social reformers preached the doctrine of 'One Caste, One Religion and One God?

Mount Everest is located in the Himadri (or Great Himalayas) range, which is the highest and most continuous mountain range in the world.Understanding the RangesTo understand why "The Great Himalayas" is the correct choice, it helps to look at how the Himalayan system is layered from North to South:The Great Himalayas (Himadri): The innermost and loftiest range. It contains almost all the prominent peaks, including Mount Everest ($8,848.86$ meters), Kanchenjunga, and Lhotse.The Lesser Himalayas (Himachal): Located south of the Himadri, this range is known for its famous hill stations like Shimla and Mussoorie.The Shiwalik Range: The outermost range of the Himalayas, consisting of unconsolidated sediments.Why the other options are incorrect:The Sivalik Range: These are the "foothills" of the Himalayas. Their average altitude is much lower ($900$ to $1,100$ meters).Nilgiris Range: These are located in Southern India (part of the Western Ghats), thousands of miles away from the Himalayas.Aravalli Range: One of the oldest fold mountain systems in the world, running through Rajasthan and Haryana; it is not part of the Himalayan system.