Generally, the sun observes a solar cycle of eleven years. In this cycle, there are fluctuations in the activity, such as the ejected levels of solar radiation, and in the appearance of the sun, such as changes in the amount and size of sun spots, solar flares and other phenomena that occur on the sun's surface.
These changes also affect phenomena on earth, especially the auroras.
Let's do this by process of elimination: A cannot be the answer because glucose is broken down, not built up or synthesized. B is ruled out for the same reason. D is incorrect because transpiration results in water loss, not energy gain. The only correct answer choice is C respiration, specifically by the process of substrate-level phosphorylation during glycolysis in order to break down glucose into two pyruvate molecules and two net ATP
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It's solar, because s</span>olar energy is a renewable resource that is virtually endless as long as the sun shines.<span />
