So all we know is that the student stated something ("<span>if plants are added to an indoor environment the air quality will improve
"). This is only a statement - it's not a test whether this statement is true yet.
So the correct answer is: it is a hypothesis.
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<span>Fermentation is a metabolic process that converts sugar to acids, gases, or alcohol. It occurs in yeast and bacteria, and also in oxygen-starved muscle cells, as in the case of lactic acid fermentation.</span>
The most important function of osmosis is stabilising the internal environment of an organism by keeping the water and intercellular fluids levels balanced. In all living organisms, nutrients and minerals make their way to the cells because of osmosis. This obviously is essential to the survival of a cell.
