Explanation:

The idea of One Nation, One Election is about structuring the Indian election cycle in a manner so that elections to the Lok Sabha and the State Assemblies are synchronised together so that the election to both can be held within a given span of time.
Advantages

• Help keep a check on the poll expenses, party expenses, etc. and also save public money.
• Reduce the burden on administrative setup and security forces.
• Ensure timely implementation of the government policies and also ensure that the administrative machinery is engaged in developmental activities rather than electioneering.
• Solve the problem of governance on the part of the politicians who are ruling. It is generally seen that for short term political gains from a particular assembly election, ruling politicians avoid taking a harsh long term decision which can ultimately help the country in the long run.
• Provide more time to all the stakeholders i.e. political parties, Election Commission of India (ECI), paramilitary forces, civilians for the preparation of elections once in five years.

Hence all statements are correct.