Answer: A.They often use up resources that other organisms need.
Step-by-step explanation:
A nonnative species is the one which is either intentionally or accidentally introduced into a new habitat. This species is capable of competing with the native species for resources like water, food and mates. This may result in the decline of the native species due to mortality of the members of the native species, migration and extinction. Therefore, the biodiversity of the region will decrease.