Zebra Mussels Were Brought to North America from Europe and Have

Zebra mussels were brought to North America from Europe and have rapidly spread through the Great Lakes and the Mississippi River.The adults attach to boats, piers, and other hard surfaces.They feed on plankton, clarifying the water but drastically decreasing the food available for native mussels and fish such as salmon and whitefish.The clearer water also promotes toxic algal blooms.Zebra fish can breed in a wide range of temperatures.A zebra mussel lives five years and produces five million eggs, of which 100,000 reach adulthood.The offspring of a single mussel will produce half a billion adult offspring.They have quickly become a major pest species in North America, although they were not pests in their native Europe.

A scientist suggests limiting mussel populations by introducing a predator of zebra mussels into the waterways.In the past, such biological control has had varying effects, depending on the species involved.In this case, which situation is the least likely outcome of this form of biological control?

A) The predator brings mussel populations under control and a balance is maintained.
B) Introduction of a new predator species causes a further increase in toxic algal blooms.
C) The predator has no natural enemies in the waterways; its population soars and it also becomes a pest.
D) The predator prefers native prey; the mussel population does not change, but some native populations are decimated.
E) Both the zebra mussel and the introduced predator outcompete native species, leading to decreased biodiversity in the waterway.