The specialized cell types in the body of amulticellular organism are different from each other chiefly because
(a) each cell type contains different genes.
(b) different genes are switched on in different celltypes.
(c) some cell types have lost some of the genes that were present inthe fertilized egg.
(d) the fertilized egg divides by cell divisions that do not give riseto genetically identical cells.
(e) the different cell types contain fundamentally differentorganelles.