For a spontaneous decay, which of the following is correct?

mass of daughter nuclei is less than the mass of parents nuclei mass of daughter nuclei and parent nuclei is same mass of daughter nuclei should be more than the mass of parent nuclei none of these

mass of daughter nuclei is less than the mass of parents nuclei

For a spontaneous decay mass of daughter nuclei is less than the mass of parents nuclei. This difference in mass appears as kinetic energy of the products.