The correct answer is c) Religious sensitivities.
The Enfield P-53 rifle was a muzzle-loading rifle that was introduced in 1853. It was a major improvement over the previous rifles used by the British army, and it was quickly adopted by many regiments. However, the rifle was also rumored to use cartridges that were greased with animal fat. This was a major problem for many Indian soldiers, who were Hindus or Muslims and who considered it sacrilegious to touch or consume animal products.
The rumors about the cartridges caused a great deal of unrest among Indian soldiers, and it was one of the factors that led to the Sepoy Mutiny of 1857. The mutiny was a major uprising against British rule in India, and it resulted in the deaths of many British and Indian people.
The other options are not correct. The Enfield P-53 rifle was not technologically superior to other rifles of its time, and it was not particularly expensive to procure. It was also not difficult to handle.
The introduction of the Enfield P-53 rifle was a major trigger for the Sepoy Mutiny of 1857 because it offended the religious sensitivities of many Indian soldiers.