The correct answer is (b) Atkinson.
The book Himalayan Districts was written by William Edward Atkinson, a British civil servant who served in India from 1833 to 1858. The book was published in 1882 and is a comprehensive history of the Himalayan region. It covers topics such as the geography, history, culture, and people of the region.
The other options are incorrect.
(a) Gardner is not the author of Himalayan Districts.
(c) Shekhar Pathak is a contemporary Indian author who has written several books on history and culture. However, he is not the author of Himalayan Districts.
(d) Maula Ram is a 19th-century Indian freedom fighter who was involved in the Indian Rebellion of 1857. He is not the author of Himalayan Districts.