Which of the following is true about natural selection? a. natural selection does not cause a species to change. b. natural selection is the only cause of changes in a species. c. natural selection usually causes a species to change suddenly. d. natural selection usually causes a species to change gradually.

Hydrilla (hydrilla verticillata) is an invasive aquatic plant and one of the most serious aquatic pests in florida. hydrilla has already been introduced to hundreds of bodies of water throughout florida, hydrilla is difficult to control because it grows rapidly and survives in many different water depths and conditions. hydrilla • describe how hydrilla affects native plant and animal species. include both a biotic and an abiotic limiting factor. • suggest one biotic and one abiotic recommendation that could slow the spread of hydrilla