All layers are incredibly important. If we didn't, we would die very quickly and life would be inhabitable. The radiation from the son would kill us. The heat from the sun would dry up water and kill crops leaving us with no food/water.
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Moose since most live freely and are not feed and maintained by humans
The answer is - Sunspots.
Sunspots are dark in appearance, but only on a visible light, and this is due to the fact that they are much cooler than the surrounding areas, but that doesn't mean by any means that the sunspots are cool, on contrary, they are very hot too. Sunspots actually are storms that appear in the lower atmosphere of the sun.