Correct Answer: Persian

Solution : The correct answer is Persian.

The work of Raja Ram Mohan Roy, titled "Gift to Monotheists," was originally written in Persian. He was a prominent Indian social reformer and intellectual who wrote and translated various works to promote monotheism and religious reform during the 19th century. Persian was a significant language for intellectual and literary discourse during that time, and many of his writings were in Persian, which allowed them to reach a broader audience in India and beyond.