In lattice every two elements having least upper bound and greatest lower bound .
So in each sublattice also least upper bound element and greatest lower bound element is compulsory needed.
D24={1,2,3,4,6,8,12,24}
lattice is
Sublattices are ={1,2,4,8,24}
{1,3,6,12,24}
{1,2,4,12,24}
{1,2,6,12,24}
Hence total of 4.