Answer:
D. Native plant species are being crowded out.
Step-by-step explanation:
The increasingly widespread presence of exotic organisms (many of which become invaders) in different regions of the planet has led to the emergence of a line of research in ecology focused on biological invasions.
Invasive alien species are recognized as one of the major causes of biodiversity loss on the planet, and given the global increase in the flow of people and goods, the potential for invasive species is increasingly widespread, increasing their environmental impacts.