Answer:
India's partitioning was done because of religious reasons, while Vietnam's partitioning was done because of political reasons.
Step-by-step explanation:
Both India and Vietnam experienced partitioning during the 20th century, and both of them after they gained independence from their colonizers. There is a big difference between the reasons for partitioning between these countries though, and there is also a big difference in the fact that India never reunited, while Vietnam did.
The partitioning of India happened because the British thought it would be a good idea to put borders and form separate countries where there were religious boundaries. Based on this, West Pakistan and East Pakistan were separated where the population was mostly Muslim, while India remained predominantly Hindu. This did not result in peace but there was large-scale violence.
In Vietnam, the partitioning occurred because of political ideologies. The North was communist while the South supported the king. This led to internal war, later with foreign intervention as well, and the country was divided into North Vietnam and South Vietnam. This didn't last long though and the country was reunited, with the communist fraction managing to take over.