At present, the rural social endowment insurance implements a nationwide unified real-name personal account according to the ID card number of the insured, and implements the payment determination type, which is mainly based on personal accounts. The payment standard is low and can be transferred from person to person. It is suitable for the flexibility of farmers' characteristics. Social endowment insurance system. This flexible social endowment insurance system has been piloted in Beijing's Daxing District, Shanxi and other places, showing good adaptability and scalability. What is the most accurate expression of the main meaning of this passage? ['Rural social endowment insurance is mainly based on the individual account of the insured.', 'Flexible social endowment insurance system shows good adaptability and scalability in rural areas.', 'Low standards for rural social endowment insurance contributions.', 'Rural social endowment insurance can be transferred from person to person.']