Which empire united most of india, built roads and established free hospitals and veterinary clinics?

the British Empire

Explanation:

The British Empire was the empire that manged to control the largest territory in the human history. Part of its colonial territory was in South Asia, or rather India. The British were superior in military, economic, and political sense, so they did not had any big problems when it came to invading India. The British managed to gain lot of wealth from India which was of course not seen fondly by the local population, and it also did some terrible things there, but there were also some positives. India got its first road network, which greatly helped in connecting the vast country. Lot of free hospitals were opened for all the people, as well as lot of veterinary clinics for the animal health, both things being very positive for the poor population.

there were abundant sources of fuel nearby