The correct answer is - D. was divided.
A series of revolutions in Indochina broke up against the French rule in the region, and Vietnam was not an exception. The Vietnamese were victorious against the French, but instead of bringing them peace and prosperity, it brought division and unrest in the country.
The north was ruled by the communist party, having the support of USSR and China, while the south was ruled by the Vietnamese emperor, having support by France and the USA.
Soon after a bloody war broke up between the north and the south, and lots of people lost their lives and homes in it.