What must public retirement funds be in terms of structure?

Public retirement funds must be independent and separate to ensure their operation aligns with the principles of financial responsibility and accountability. This structural independence helps safeguard the funds from political influence, ensures that the assets are managed with a focus on the beneficiaries' long-term interests, and protects the integrity of the retirement system from any potential conflicts of interest.

By maintaining this separation, public retirement funds can operate more effectively, providing a stable source of retirement income for public employees. This independence is crucial in building trust among stakeholders, ensuring that the funds are set aside for their intended purpose, and can be managed according to sound financial principles.

Other choices do not accurately capture the essence of the structural requirements for public retirement funds. While some may reflect aspects of their operation, they do not emphasize the need for independence and separation from external pressures and interference.