What is an invasive species?
A - A species that is continuously expanding its range
B - A non-native species whose introduction into an area has caused economic or ecological harm
C - A species that is living outside of its native environment and was brought there by human activity
D - A species that is naturally found in an area and was not introduced by humans
E - Any introduced species that survives and thrives in its new environment
Answer: B - A non-native species whose introduction into an area has caused economic or ecological harm