Where are you most likely to find primary succession

a. in an area that was severely clear-cut
b. in an area that was covered by floodwater
c. in an area that was severely burned
d. in an area uncovered by a retreating glacier

The answer is D. in an area uncovered by a retreating glacier (Apex)

D. in an area uncovered by a retreating glacier

A succession is progressive change in a biological community sustaining in an ecosystem with respect to changes in abiotic factors and time until an ecosystem attains stability. Primary succession is the first and primitive level of succession which depicts a region which was previously barren and cannot sustain any life form. A retreating glacier is an example of primary succession because the rocks left by the glacier are barren and unfertile. Therefore, cannot support plant growth. Lichens being the first species will live on these barren rocks and acids produced by them will remove the compaction of rocks and convert them into soil particles which can support the growth of other plant species. These lichen species are known as pioneer species.  

one would be wind another would be water density