Final answer:
Copyright laws exist to d. limit free-riding, providing creators with the exclusive rights to use and distribute their work to prevent others from exploiting it without contributing.
Step-by-step explanation:
The question is asking why copyright laws exist. The correct answer is to limit free-riding. Copyright laws are a part of intellectual property law that grant creators the exclusive right to use and distribute their work, and thus prevent others from using the work without permission---a restriction aimed at reducing the tendency among individuals to use, or 'free ride' on, the works created by others without contributing themselves.
This contrasts with the 'tragedy of the commons', which refers to the situation in which a resource is depleted as individuals act according to their self-interest and overuse common goods. Government regulation, including copyright laws, help to mitigate the effects of free riding by protecting the investments of creators and ensuring they receive compensation for their work, encouraging them to continue producing.