The graph above depicts the human population of the world from 1050 to 2050 (projected). With an ever increasing human population, we pose a threat to our own planet in many ways. In terms of sustainability, which of these is not vital to this population growth? A) the air quality is deteriorating B) our natural resources are depleting C) birth control policies should be strictly enforced D) the food industry can't keep up with the demand of a growing population