bio help please!!?

Yellow crazy ants live in large colonies, scouring the forest floor for food and space. Which situation is most likely occurring in this ecosystem?

a The ants are not likely to change the structure of the ecosystem.

b Native land crab species will quickly develop defenses against the ants.

c Many forest floor-dwelling organisms will be displaced by the ants.

d The ants will eventually destroy the entire ecosystem.

When new bare land has been created or the ecosystem has been severely damaged by a fire, what is likely to occur?

a The climax community begins the process of succession.

b Pioneer species begin the process of succession.

c A completely new ecosystem evolves at the location.

d Only nonnative species replace the native species.