Which of these is a disturbance that would trigger primary succession?

Question

livestock grazing
wildfire
glacial retreat
road construction

Answer 1

Glacial retreat is a disturbance that would trigger primary succession. This process occurs when a glacier moves away, exposing bare rock and creating a new substrate for life to colonize. The other options—livestock grazing, wildfire, and road construction—are more associated with secondary succession, as they typically affect areas where soil and some biological components are already present.