Present one example of a human activity that threatens
ecosystems and biodiversity.

One example is overpopulation. Meaning the more people there are in a place, the more room there needs to be. This then leads to deforestation, destroying animals habitats forcing them to leave. The more animals that leave, the less animal diversity there is.

if you look up in the top right corner you'll see your current profile picture, click than click "view profile" you'll be able to change it there.