Question

why are invasive species dangerous to the environment?
○ they pollute the environment.
○ they are always predators.
○ they threaten biodiversity.
○ they bring abiotic factors.

Explanation:

• Option "They pollute the environment": Invasive species don't primarily pollute; pollution is from substances like chemicals, so this is incorrect.
• Option "They are always predators": Invasive species can be plants, pathogens, etc., not always predators, so this is wrong.
• Option "They threaten biodiversity": Invasive species compete with native species for resources (food, habitat), outcompete them, and can cause native species to decline or go extinct, thus threatening biodiversity. This is correct.
• Option "They bring abiotic factors": Abiotic factors are non - living (like water, temperature), and invasive species are biotic (living), so this is incorrect.

Answer:

C. They threaten biodiversity.