Answer:
Many rocky coasts occur along active margins. This is because -
( a ) active margins often experience repeated uplift, and thus the waves have not had sufficient time to erode the land surface down to sea level.
Step-by-step explanation:
Active Margin -
The Active Margin are present at the edge of the continental plate that is crashed in an oceanic plate . It is possible that the active margins are uplifted rocky coasts . Hence , the wave does not have sufficient time to erode to the surface down the sea level . therefore , many rocks are found along this active margin . As , due to regular uplifts and hence , the waves do not have sufficient time to erode the land surface down to sea level .