C. Vegetation
because even though cows are important, all life is and not just that species and then cars and factories are unnatural and would not be critical for the carbon cycle in nature.
A . Value because that’s your valued opinion
The answer is a. accessible population because an accessible population is the portion of the target population to which the researcher has reasonable access.
Most bacteria are heterotrophic decomposers, which means they depend on other organisms for food and feed on dead matter.
Groundwater is the water found underground in the cracks and spaces in soil, sand, & rock.