Saigon, the city renamed in 1976 after the reunification of its country, is now called

The correct answer is B, Thailand. The kingdom was called Siam until 1939, when it took the name Thailand, understood as the land of the free, a name that fits the fact that it is the one country of South-East Asia never ruled by a European power. Option A is wrong because Myanmar was called Burma until 1989, and its own earlier capital Rangoon became Yangon at the same time. Option C is wrong because Vietnam formed part of French Indochina, and it is its southern city Saigon that was renamed, becoming Ho Chi Minh City in 1976. Option D is wrong because Cambodia was known as Kampuchea for a period and in older history as Kambuja, the land of the Khmer kings who built Angkor Wat. Learning the four South-East Asian changes as one group, Siam, Burma, Kampuchea and Saigon, keeps them apart in the examination hall.

The correct answer is C, 1972, the year the island became a republic and took the name Sri Lanka in place of Ceylon. Option A is wrong because 1948 is the year it became independent, while still called Ceylon, so the two dates are often mixed up and the question is set precisely for that reason. Option B is wrong because 1956 belongs to the language legislation of the island and to no change of the country's name. Option D is wrong because 1989 is the year Burma became Myanmar, which is the other favourite date in this group. The island's capital is another trap worth noting: the commercial capital is Colombo but the administrative and legislative capital is Sri Jayawardenepura Kotte, and papers often ask for the second name. So the chain to remember is independence in 1948, republic and the name Sri Lanka in 1972.

The correct answer is B, Ghana. The British colony of the Gold Coast, named for the gold traded from its shore, became independent in 1957 under the name Ghana, which was taken from a medieval West African empire, and it was the first colony of sub-Saharan Africa to win its freedom. Option A is wrong because Nigeria kept its name, which comes from the river Niger, when it became independent in 1960. Option C is wrong because Ivory Coast, which prefers the French form Côte d'Ivoire, has carried that name throughout and is a different country altogether. Option D is wrong because Sierra Leone, the land of the lion mountains, also kept its older name. In this group the renamed countries are the Gold Coast to Ghana, Nyasaland to Malawi, Bechuanaland to Botswana and Basutoland to Lesotho.

The correct answer is B, Burkina Faso, which was called Upper Volta after the branches of the river Volta that cross it and took its present name in 1984; the new name is drawn from two of its own languages and is read as the land of upright people. Option A is wrong, and it is the usual trap, because Benin is the new name of Dahomey, which was renamed in 1975, so the two West African pairs are offered against each other. Option C is wrong because Mali was French Sudan before independence, which is a different old name worth remembering separately. Option D is wrong because Niger has kept its name, which it shares with the river and with Nigeria. The safe way to hold this group is as three lines: Upper Volta to Burkina Faso, Dahomey to Benin and French Sudan to Mali.

The correct answer is B, Zambia and Zimbabwe. Northern Rhodesia became Zambia on independence in 1964 and Southern Rhodesia became Zimbabwe in 1980, the new name being taken from the stone ruins of Great Zimbabwe. Option A is wrong because it reverses the pair, which is exactly the error the question is built to catch; the way to keep it straight is that the northern country took the shorter name. Option C is wrong because Malawi was Nyasaland, the third territory of the old federation, and not a Rhodesia at all. Option D is wrong because Namibia was South West Africa until 1990 and Botswana was Bechuanaland until 1966, which belong to a different group of changes. The three territories of the Central African Federation, Northern Rhodesia, Southern Rhodesia and Nyasaland, are best learnt as one line.