Which statement describes the process of subduction? Convection currents cause two plates to move away from each other.
A plate slides beneath another plate due to convection currents and gravity.
Materials are heated and transferred within Earth’s interior by density.
Heat cycles in the mantle cause plates to constantly move.

answer; eliminate parking problems in cities, because a car took up only half as much space as a horse and buggy;

even though you have attached neither the chart nor the generalizations, i have located them online. the right answer is d, since they are asking you about a generalization. you can only infer from the chart that between 2008 and 2009 the number of employed workers decreased significantly (from over 115 millions to 107 millions approximately), which signals some type of economic crisis.