Which of the following is the most important cause for animals and plants being driven to extinction?

From the evil quartet, habitat loss and fragmentation due to over population, urbanization and industrialization is the major cause of extinction. Loss of habitat and fragmentation endangers the survival of wildlife species by exposing them to a higher degree of pollution. Tropical rainforests, previously covering an area of 14%, have been reduced to 6% in recent times. This has led to the extinction of several species over the last few centuries.