for the past 20 years, the population of the invasive asian carp in the mississippi river has skyrocketed while populations of native species have declined. which of the following conclusions provides the best explanation for this phenomenon?
a. the carp out-competed the native species for food and space.
b. the food sources preferred by the carp increased.
c. the native species contracted a virus that the carp were immune to.
d. the native species migrated to new areas, while the carp remained.