The problem of Partition caused the largest level of challenges when British control ended in India.  The largest two religious groups in India were those of the Hindu faith and those of the Islamic faith.  There were Hindus and Muslims in nearly every village and city in India.  The arbitrary line that was drawn to divide India and Pakistan heightened tensions between both groups and instigated communal riots between both groups in a setting where the government was unable to fully address such challenges.  When busloads of Hindus were burned by Muslims who were seeking revenge for trains of Muslims burned by Hindus, one could say that this was a major problem for India.  At the same time, the idea of the diversity of India posed another hurdle for the new nation.  India was a nation with more than Hindus and Muslims.  So many groups were unified with a common enemy in the British.  The Anglo departure created a vacuum where these different groups started to view one another with skepticism.