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How are the high islands of the pacific formed? a. by connected coral reefs called atolls b. by lagoons c. by moving glaciers d. by underwater volcanoes

How would i answer this for an exam?

What was the most difficult obstacle to overcome in the creation of an autonomous state after indian independence was achieved? a british willingness to go to war to retain the region b. religious differences between hindus and muslims c. ethnic differences between tribal regions d. indian princes' inability to decide on a format of government