What are the three different methods that can lead to primary succession?

Examples of disturbances that cause primary succession include retreating glaciers, volcanic eruption and the erosion of sand dunes. Human activity can also be a cause of primary succession, such as the creation of a paved surface. These types of disturbances leave bare rock exposed or otherwise accessible.

Explanation:

because the light is a great source of energy for the plants to survive. (i hope this )

correct answer is a. and d.