Among the four major causes of biodiversity loss (the 'Evil Quartet'), which of the following correctly identifies the most important cause and the specific group of organisms most severely affected by its fragmentation aspect?

Step-by-step solution

According to NCERT, 'Habitat loss and fragmentation' is the most important cause driving animals and plants to extinction. When large habitats are broken up into small fragments due to various human activities, mammals and birds requiring large territories, as well as certain animals with migratory habits, are badly affected. This leads to severe population declines. While over-exploitation and alien species invasions are also part of the 'Evil Quartet', they are not the primary cause. Furthermore, fragmentation sp