Answer C, I think. Hope to help :)
Answer:
Declining crude birth rates.
Explanation:
Birth rate may be defined as the number of births takes place per year per thousand of the population. The birth rate and death rate may change the population dynamics.
The developing countries shows the expanding population graph as they have more number of people of the reproductive age. The advancement in the medical field results in the decline birth rate that causes the decline of the nature resources.
Thus, the answer is declining crude birth rates.
Nervous muscle action pressure
Answer:D) Decomposers break down the remains of producers and consumers
Explanation:A biotic pool is a tidal pool with diverse and changing habitats of living factors. We can say they are important mini ecosystems within the larger ecosystem.
The abiotic pool involves the elemental phases of nature,the non living parts of the ecosystem. Decomposition (break down) of elements/organic compounds is the characteristic bridge between both pools into what is known as nutrients.
This tell us that the ultimate dead part of producers and consumers are used up in this process.
Some of the nutrients released in the biogeochemical cyclic process includes sulfur and phosphorus and they move through the ecosystem.
Note: The biogeochemical cycle is a pathway of movement for chemical elements.
The chemical elements in nature moves through both biotic and abiotic components via abiotic and biotic interaction in the ecosystem
Few abiotic factors includes rocks, air, water, and chemicals while biotic factors includes living organisms activities.
All living and non living elements of nature play vital roles in the great biogeochemical cycle.
D. Phenotype because a phenotype is observable traits
