Answer:
C climate change
Explanation:
because  biologists estimate that 35% of animals and plants could become extinct in the wild by 2050 due to global climate change. If we can sufficiently reduce greenhouse gas emissions, many of them will still have a chance to survive and recover. NASA scientist James Hanson has warned that in order to maintain a climate similar to that under which human civilization developed and similar to that which so many organisms are adapted, we need to quickly reduce the carbon dioxide in our atmosphere to 350 parts per million (ppm). Before the industrial revolution, atmospheric carbon dioxide levels rarely rose above 280 ppm; during the 2014 calendar year, carbon dioxide levels fluctuated between 395 and 402 ppm.
To highlight the significance of the number 350, the Center for Biological Diversity has compiled a list of 350 species found in the United States and its territories which are threatened by climate change.
