I believe that the answer is D. lichens growing on cooled lava. Hope it helps.
Answer:
A feedback loop is a biological occurrence where the output of a system amplifies the system (positive feedback) or inhibits the system (negative feedback).
Explanation:
Example, during blood clotting, a cascade of enzymic proteins acitvates each other, leading to the formation of fibrin clot that prevents further blood loss.
Earthquake, volcano and continental shifts
Catalyst. A catalyst is a substance that increases the rate of a reaction without being consumed the rate of a reaction without being consumed in process, or being chemically altered. There are many enzymes present in cells, proteases, lipases, that speed up metabolism, and catalysts .
hOpe this has helped you any . >)