Primary succession is most likely caused by
(a) clear cutting
(b) climate change
(c) volcanic eruption
(d) introduced species

Answer;

(C) Volcanic Eruption

Explanation;

-Primary succession occurs in lifeless areas; regions in which the soil is incapable of sustaining life as a result of factors such as lava flows due to volcanic eruptions, newly formed sand dunes, or rocks left from a retreating glacier.

-Steps of primary succession are;

Step one- Bare rock, no organisms - Glacier leaves behind bare rock; Volcano produces bare rock with no organisms.

Step Two - Pioneer species begins breaking down rock. Pioneer species: 1st organism to live in an area. Pioneer species, usually lichens, grows on rock. Lichens secrete acids that begin breaking rock into small particles, which mix with lichen remains to begin making soil.

Step Three- More complex plants, usually mosses, begin growing when soil is deep enough, after many years; eventually replace (succeed) lichens. Tiny organisms such as insects move in, add their remains to soil.

Step Four-Larger, more complex plants: As soil gets thicker ferns succeed mosses. Grasses and wildflowers may succeed ferns. When enough soil has developed, shrubs and small trees move into the area.

Step Five-Forests: Soil may be deep enough after hundreds or thousands of years for pine or hardwood forests

The C. Volcanic Eruption

In primary succession, the ecosystem is left with only bare rock and has to start over again. Therefore, a volcanic eruption would destroy the soil in which plants grow, so it is left with bare rock.

It is not a direct variation becuase though it goes through the orgin, its curved rather than straight.