Which substance is a good natural resource because it is used by plants and in fertilizer, and sometimes can be used to keep things really cold? a. silicon b. oxygen c. krypton d. nitrogen

sexual reproduction produces offspring with novel combinations of genes. species that reproduce sexually must maintain two different types of individuals, males and females, which can limit the ability to colonize new habitats as both sexes must be present.

well, that's easy; the answer's c, "it reduces contamination of the water and substrate of the estuary."

there are so many examples for that in different areas, like biology experiment carried out in our lab recently.

here's one link: