Extinction of Steller's sea Cow and passenger pigeon is due to

Over exploitation by human

The correct answer is Option (2) → Over exploitation by human

Over-exploitation refers to the excessive and unsustainable harvesting of a species by humans. In the case of Steller's sea cow, the uncontrolled hunting by sailors and explorers led to the rapid decline and eventual extinction of this species . This serves as a historical example of the severe consequences of over-exploitation on vulnerable and slow-reproducing species.

Humans have always depended on nature for food and shelter, but when ‘need’ turns to ‘greed’, it leads to over -exploitation of natural resources. Many species extinctions in the last 500 years (Steller’s sea cow, passenger pigeon) were due to overexploitation by humans. Presently many marine fish populations around the world are over harvested, endangering the continued existence of some commercially important species.

Habitat loss and fragmentation: This is the most important cause driving animals and plants to extinction. The most dramatic examples of habitat loss come from tropical rain forests. Once covering more than 14 per cent of the earth’s land surface, these rain forests now cover no more than 6 per cent. They are being destroyed fast.

Alien species invasions: When alien species are introduced unintentionally or deliberately for whatever purpose, some of them turn invasive, and cause decline or extinction of indigenous species.

Co-extinctions: When a species becomes extinct, the plant and animal species associated with it in an obligatory way also become extinct. When a host fish species becomes extinct, its unique assemblage of parasites also meets the same fate.