Answer: A.) They are destructive to native species and have no natural predators.
An invasive species is a species which when introduced or immigrated to a new ecosystem compete with the native species for resources as a consequence, this species is responsible from elimination, extinction and migration of native species living in an ecosystem. Cane toads in Australia are considered as an invasive species rather than simply nonnative because they are destructive to native species and have no natural predators.
