Answer:
d. all of the above
Step-by-step explanation:
For a long time, China has been an example of what not to do to achieve environmental sustainability. In 2005, it ranked 133 out of 146 countries for its environmental efforts. China faces serious environmental problems, ranging from severe air and water pollution, deforestation, desertification and extinction to overpopulation.
Since the Great Leap Forward of Mao, natural ecosystems have been destroyed in favor of agriculture, steel production and, more recently, goods for export. In 1994, "sustainable development" became a national strategy, but economic growth remained the priority, according to Liu.