Answer: C. A court rules that a state is allowed to racially segregate restrooms because earlier courts ruled in favor of segregated buses.
The principle of precedent is the idea that a previous legal case is either binding, or persuasive for a court when deciding subsequent cases with similar facts. The concept allows courts to yield predictable and consistent results. This is one of the most important values of common-law legal systems. In this case, the fact that earlier courts ruled in favor of segregated buses is very significant for the court's subsequent decision to allow segregated bathrooms.