During Succession, Two Plant Species Become Established at Different Times

During succession, two plant species become established at different times.Species A is a perennial with roots that secrete chemicals to maintain a distance between members of the species and similar species.Species B is a low-growing annual with nitrogen-fixing bacteria in its root nodules.Which (if either) of these two species most likely appears first during succession, and why?

A) Species A likely appears earlier because it facilitates other species by modifying the ecosystem so that later species can colonize.
B) Species A likely appears earlier because it inhibits other species by preventing the establishment of unsuitable species.
C) Species B likely appears earlier because it facilitates other species by modifying the ecosystem so that later species can colonize.
D) Species B likely appears earlier because its inhibitory interactions are necessary to prevent the establishment of unsuitable species.
E) Both species likely appear early in succession, so their positive and negative interactions can work together throughout the process.