I think its the atmosphere ?????
The biome that has infertile soil, principally oxisols, to which the vegetation <span>has roots systems that capture nutrients from litter decay, is the tropical rainforest.
Soil types are highly variable in the tropics and are the result of a combination of several elements or variables which includes climate, vegetation, topographic position, parent material and also the soil age. Most of the tropical soils are described by leaching and poor nutrients. It also has two classifications: namely the ultisols and oxisols. Ultisols are known as well-weathered, acidic red clays soils. They are deficient primarily in major nutrients such as potassium and calcium. Oxisols are also an acidic type of tropical soil. However, they are well drained compared to the ultisols.
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The correct answer among the choices provided is option A. Lung capillaries are responsible for exchanging carbon dioxide for oxygen from the air. Blood that comes from the heart gets oxygen from the alveoli. The carbon dioxide in the blood goes into the alveoli at the same time.
Create a hypothesis read more information then see if her answer was correct
