Which of the following statement is correct according to Clausis statement of second law off thermodynamics?

• It is possible to transfer heat from a body at a lower temperature to a body at a higher temperature.
• It is impossible to transfer heat from a body at a lower temperature to a body at a higher temperature, without the aid of an external source.
• It is possible to transfer heat from a body at a lower temperature to a body at a higher temperature by using refrigeration cycle.
• none of the above