How often must families demonstrate their rights under free movement?

The correct answer indicates that families do not need to demonstrate their rights under free movement on a regular basis. Once individuals have established their rights to free movement, they generally retain those rights without needing to reprove their status periodically. This aligns with the principle that the right to free movement is established through legality, rather than requiring ongoing proof.

This lack of requirement for regular demonstration helps ensure stability for families who have moved across borders within the context of the law. It prevents unnecessary bureaucratic repetition and aids families in settling into new environments without the burden of continuous administrative checks.

In contrast, the other options entail periodic requirements that do not align with the principles of free movement. Such requirements could potentially create hurdles for families, making the process of exercising their free movement rights more complicated than intended. Thus, maintaining the idea that there is no need for regular demonstration reinforces the intention behind free movement policies.