Figure 54-1 ​

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In Experimental Condition 2 of the accompanying figure, the distribution of Chthamalus suggests that:

A) interspecific competition kept Chthamalus from extending lower into the intertidal area.
B) intraspecific competition kept Chthamalus from extending lower into the intertidal area.
C) a limiting factor kept Chthamalus from extending lower into the intertidal area.
D) a barnacle parasite kept Chthamalus from extending lower into the intertidal area.
E) predation kept Chthamalus from extending lower into the intertidal area.