Final answer:
The false statement about nonnative species is that they can be introduced within their natural range. Nonnative species, introduced outside of their natural habitat, can become invasive and significantly affect ecosystems.
Step-by-step explanation:
The statement about nonnative species that is not true is c. They can be introduced within their natural range. By definition, nonnative species are introduced outside of their natural ranges, often by human activities. These introductions can result in non-native species becoming invasive species, which can significantly alter or damage the ecosystems they invade through competition for resources, predation, and disease. While non-native species can have positive impacts on ecosystems, such as by filling vacant niches or providing new resources, their negative impacts are often far more significant, leading to reduced biodiversity, extinction of native species, and altered community structures.