The correct options are
A maintenance of ecological processes and life-supporting systems.
B preservation of diversity of species.
D sustainable utilization of species and ecosystems.
Conservation simply implies the sustainable use as well as management of natural resources which include wildlife, water, air, and earth deposits. It is important to conserve living resources to maintain ecological biodiversity. Even if one aspect of the ecosystem, say wildlife, is affected, the consequences reflect on all other aspects of ecosystem as well.