Option D : Habitat loss and fragmentation is considered the most important cause driving extinction of species among 'The Evil Quartet'.

The 'Evil Quartet' refers to the four major causes of biodiversity loss: habitat destruction and fragmentation, over-exploitation, pollution, and invasive species. Of these, habitat loss and fragmentation is generally considered the most significant cause, as it directly affects the availability of the resources and space that organisms need to survive. It can be caused by a variety of human activities, including deforestation, urbanization, and agriculture. This loss of habitat leads to smaller, more isolated populations, which are more vulnerable to other threats and have a higher risk of extinction.