The primary cause of the Revolt of 1857 was discontent among:

Indian sepoys in the British East India Company's army
Zamindars and peasants
Religious leaders
Indian princes

The primary cause of the Revolt of 1857 was discontent among Indian sepoys in the British East India Company’s army. The sepoys were Indian soldiers who were recruited to fight for the British East India Company. They were paid poorly and treated poorly by their British officers. In addition, the sepoys were required to use a new type of rifle that used cartridges that were greased with animal fat. This was offensive to the sepoys, who were Hindu or Muslim and did not want to touch animal fat.

The sepoys also felt that the British were interfering in their religious practices. For example, the British had banned the practice of sati, which was the practice of burning a widow on her husband’s funeral pyre. The sepoys also felt that the British were not respecting their culture and traditions.

All of these factors led to a great deal of discontent among the sepoys. In 1857, the sepoys at Meerut mutinied and killed their British officers. This mutiny quickly spread to other parts of India, and soon the entire country was in revolt. The Revolt of 1857 was a major turning point in Indian history. It led to the end of the British East India Company’s rule in India and the beginning of direct British rule.

The other options are not correct because they were not the primary cause of the Revolt of 1857. Zamindars were Indian landlords who were not happy with the British government’s policies, but they did not play a major role in the Revolt of 1857. Peasants were also unhappy with the British government’s policies, but they were not as organized as the sepoys and did not play a major role in the Revolt of 1857. Religious leaders were also unhappy with the British government’s policies, but they did not play a major role in the Revolt of 1857. Indian princes were not happy with the British government’s policies, but they did not play a major role in the Revolt of 1857.