Which environmental changes occur fastest. volcanic eruption. pond succession. decomposition of a tree. regrowth of forest after volcanic eruption

The correct answer is A
volcanic eruption
Volcanic eruption is defined as the sudden rush of energy materials such as gas,lava and steam.  all the others processes takes a great deal of time. For example decomposition takes a long time. Pond succession is dependent on settling of debris and hence takes a long time. regrowing of a forest after a a volcanic eruption can span several years,especially if indigenous trees are the main tree species.

The answer to this will be from your lab notes/procedure. it would be best to ask another student who participated in the lab as we do not know what was done, what enzyme or if the temperature is celsius or fahrenheit. if i were to guess though i'd say the rate stopped due to enzyme denturing at high temperature