An annular solar eclipse happens when the Moon covers the Sun's center, leaving the Sun's visible outer edges to form a “ring of fire” or annulus around the Moon. The ring of fire marks the maximum stage of an annular solar eclipse<span>.
</span><span>https://www.timeanddate.com/eclipse/annular-solar-eclipse.html
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The answer to that is sunlight. If you need an explanation tell me but I think it’s self explanatory :)
An endoskeleton of calcified cartilage
Since most fungi and decomposers are Saptotrops, The answer is most likely A; Saprobic.