USA HISTORY

Detailed explanation-1: -Detailed Solution The correct answer is Agricultural practices.

Detailed explanation-2: -When demographers attempt to forecast changes in the size of a population, they typically focus on four main factors: fertility rates, mortality rates (life expectancy), the initial age profile of the population (whether it is relatively old or relatively young to begin with) and migration.

Detailed explanation-3: -One of the main reasons for the growth of cities was the Industrial Revolution, which began in England toward the middle of the eighteenth century and then spread to the United States and other parts of Europe. The Industrial Revolution contributed to the rise of factories, creating a demand for workers in urban areas.

Detailed explanation-4: -These density-independent factors include food or nutrient limitation, pollutants in the environment, and climate extremes, including seasonal cycles such as monsoons. In addition, catastrophic factors can also impact population growth, such as fires and hurricanes.