Migration is also considered as an important factor of population change justify​

Migration is an important determinant of population size as it changes not only the population size but also the population composition of urban and rural populations in terms of age composition.In India, the rural-urban migration has resulted in a steady increase in the percentage of population in cities and towns.

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the correct answer is the following is a list of inventions made in the medieval islamic world, especially during the "islamic golden age" (8th to 13th centuries),[1][2] as well as the late medieval period, especially in the emirate of granada and the ottoman empire.

science and technology in the islamic world adopted and preserved knowledge and technologies from contemporary and earlier civilizations, including persia, india, china, and greece-roman antiquity, while making a number of improvements and innovations.