C. is the correct answer, D would be too tedious for a 10 year study, knowing the growth of the country would be pointless if you're studying a city, and it's much easier to keep track of numbers through percentiles than looking at plain numbers, look at the difference between a population increase over 5 year using these two figures. 1007893456-349272929339 citizens in 5 years or a 872% increase in citizens over 5 years with a starting figure of 1007893456 people. Hope this sort of helps.