The incident that started the Sepoy Rebellion was related to a rumor about the the working conditions at trading posts. the working conditions in textile factories. the materials used to make rifle cartridges. the materials used to sew soldiers' uniforms

During the revolt of 1857, there were rumors that spread that the cartridges that are used to bombard the cities in India were greased with pig' and cow' fat.

This annoyed both Hindus and Muslims who were asked to bite the bomb shell and tear of the head part of it which was filled with animals' fat, as it was against both of their culture and religion respectively.

Many peasants were imposed heavy taxes who started to protest against British. They formed a rebellion group called Sepoy Mutiny and began to revolt against the British.

Materials used to make the rifle cartridges is the correct answer.

Explanation:

The Indian mutiny was period of uprisings in Northern and central India which lasted from 1857-1858. It is also known as the revolt of 1857. The cause of rebellion was that the Indians started to believe that the British wanted to convert them into Christianity and also the rumor that British were coating the Cartridges with cow and pig fat in the Lee-Enfield rifles to corrupt their religion. Using Cow and Pig fat was offensive for both the Hindus and Muslim soldiers. Although the British had replaced the cartridges with the ones which were coated with the Greece made of beeswax and Vegetable oils but the rumours kept spreading. The mutiny began when Mangal Pande of 34th Native Infantry killed his British Sergeant.