Invasive species often unbalance the ecosystems into which they are introduced because a. they did not co-evolve with the natural species and lack natural controls, like predators b. they breed quickly and have the potential to overpopulate an area c. they consume local resources d. none of the above

The correct answer for the question is A. they did not co-evolve with the natural species and lack natural controls like predators.

Explanation; 
Invasive species are those species that are non native to a given ecosystem of concern and also whose introduction causes or is likely to cause economic or environment harm or harm to the organisms in the ecosystem. They are considered as the second most threat to biodiversity, after habitat loss. They become competitors, predators, hybridizers,  parasites and diseases of the native and domesticated animals and plants. 

The answer is a because with out natural predators there able to eat all they want without fear of anything keeping them in check.