Answer: a. It sets precedent for other similar cases.
Explanation:
The Supreme Court is the highest court in a country and whatever decision is made by a Supreme Court is usually final and cannot be changed except in rare circumstances.
The significance of the Supreme Court ruling on a case is that it sets precedent for other similar cases. For example, the case regarding Brown v. Board of Education set precedent for others cases that has to do with desegregation.