Biology

The correct answer is: D.Because primary succession does not begin with soil being present.

In primary succession, the process starts in an environment where there is no pre-existing soil, such as on bare rock, newly formed volcanic islands, or glacial retreat areas. The lack of soil means that organisms, such as plants, cannot immediately take root.

As a result, the process of soil formation has to happen first, often starting with pioneer species like lichens or mosses that help break down rocks into smaller particles. Over time, these pioneer species contribute to the development of soil, which allows for the growth of more complex plants and the progression of ecological succession.

Since soil formation and the gradual development of a more complex ecosystem take time, primary succession tends to occur over a much longer period compared to secondary succession.

Why the other options are incorrect: