Explanation:

- Khushwant Singh (Option 3): He is the author of 'A History of the Sikhs'. A renowned Indian writer and journalist, Singh's work covers Sikh culture and history extensively.

- Amrita Pritam (Option 1): She was a celebrated Punjabi writer and poet known for works like 'Pinjar'. Her focus was more on poetry and fiction rather than historical writings.

- Bhai Vir Singh (Option 2): He was a Sikh poet, scholar, and theologian respected for his spiritual and religious works but not specifically for a comprehensive history of Sikhs.

- Gurbachan Singh Talib (Option 4): He was a scholar known for writings on Sikhism and Punjabi literature but did not author this particular historical book.