Answer: d. C (parent rock)
Soil horizons are the layers lying parallel to the surface or subsurface layers of soil. These horizons are formed in the process of soil horizon. These sequence of soil horizons is collectively called as soil profile.
The layer or soil horizon, which is least likely to be penetrated by plant roots is C horizon. The C horizon is a layer of soil, which consists of huge aggregates of parent rocks, which are unweathered or partially weathered, lying deep in the bottom of the soil profile. It does not contain organic matter. Also, the texture of the soil is not fine, instead hard rocks are present. Therefore, this layer of soil cannot be penetrated by plant roots.
Answer:
External means on the outside, so it can be something like their fur color. Some other features can be number of legs, if they have wings or not, etc.
According to the research, most of the carbon quickly enters back into the atmosphere in the form of carbon dioxide.
<h3>What is the carbon cycle?</h3>
It is the process that describes the flow of carbon (in the form, for example, of carbon dioxide) in the atmosphere, the ocean, the terrestrial biosphere.
Thus, the CO2 in the atmosphere passes through photosynthesis to the plants, also the cycles of respiration and microbial decomposition intervene, which release new CO2 in gaseous form into the atmosphere.
Therefore, we can conclude that according to the research, most of the carbon quickly enters back into the atmosphere in the form of carbon dioxide.
Learn more about carbon cycle here: brainly.com/question/6835895
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The answer to which of the following is extrusive is letter B. lava
