Spermiogenesis / Spermatoleasis is the transformation of: (NCERT XII : 47)
1) primary spermatocytes into secondary spermatocytes
2) spermatogonium into functional spermatozoa
3) spermatogonium into primary spermatocyte
4) spermatids into spermatozoa
4) spermatids into spermatozoa