Wildlife is an asset for our environment. It needs to be protected to maintain an optimum biodiversity. Some of the reasons for extinction of wild life are:
Destruction of their natural habitats by environmental pollution, deforestation, soil erosion, overgrazing, increased urbanization, forest fires, and developmental works.
Over exploitation of the natural resource, that is pollution of air and water.
Indiscriminate hunting that is hunting for flesh and international trade in rare animals.
Therefore, the correct answer is option D.