As the Figure Below Illustrates, the Distribution of Numerous Intertidal

As the figure below illustrates, the distribution of numerous intertidal organisms is restricted to bands or zones. The upper limit to the zone is determined by tolerance to physical factors like desiccation while the lower boundary is determined by a biological interaction such as competition.
What could account for the lower limit for Semibalanus?

A) competition from adult Chthamalus living in deeper water
B) the force of the waves on the lower portions of the rock
C) predation from less tolerant predators like sea stars
D) overheating during low tide exposure