ANSWER: Biological biodiversity refers to all the different kinds of life that are obtainable in a particular ecosystem, this include all the plants and animal populations that are found in a particular geographical area.
Biodiversity supports healthy ecosystem because it enhances the productivity and the survival of the ecosystem. For instance, in a situation where there are large number of different plant population in an ecosystem, such population will present variability in genetic make up. If a negative event occur in the ecosystem, it will be possible for some plants to survive. But, in a situation where it is only one type of plant that is obtainable in the ecosystem, it will be quite easy to wipe all of them out at once. For instance, a disease outbreak can easily destroy all the plants.
"cutting down trees to build new buildings and roads", "factory and automotive emissions causing acid rain" and "redirecting and storing freshwater behind dams" exemplifies a way in which humans modify ecosystems. The correct option among all the options that are given in the question is the last option or the fourth option.
