Non-native or alien species are often introduced inadvertently for their economic and other uses. They often become invasive and drive away the local species. Exotic species have proved harmful to both aquatic and terrestrial ecosystems. For example, water hyacinth (Eichhornia crassipes) was introduced in Indian waters to reduce pollution. It has clogged water bodies including wetlands at many places resulting in death of several aquatic plants and animals.
Second major cause of species extinction is

Options

A. habitat loss and fragmentation
B. over exploitation
C. alien species invasion
D. co-extinction

Answer

C