The correct answer is B. Secondary succession
Explanation:
In ecosystems, secondary succession occurs as certain events such as fires cause vegetation to temporarily disappear from one area. However, as soil is not affected negatively, vegetation grows again after some time, which means there is a secondary growth of vegetation and changes in the structure of an ecological community.
This term applies to the situation in the 1988 fires in Yellowstone Park because the fire destroyed the vegetation in the zone temporarily, but as the soil was intact after years or decades the vegetation will grow again, although this might implied changes in the ecosystem.
A semipermeable membrane is a membrane that allows certain substances to pass through it. The most accurate definition is the third choice, "It is a barrier with tiny openings that let some, but not all, materials pass through." hope this helps:)
Hypotonic (assuming that the solution on the outside is the same solution on the inside)
Acetylcholine, sometimes shortened to ACh.