The division of each primary spermatocyte produces

The correct answer is spermatids.

Spermatogenesis refers to the procedure by which haploid spermatozoa produce from germ cells in the seminiferous tubules of the testis. The procedure initiates with the mitotic differentiation of the stem cells situated near to the basement membrane of the tubules.

The mitotic division generates two types of cells; the type B cells divide into spermatocytes. The primary spermatocyte differentiates mitotically into two secondary spermatocytes; each of the secondary spermatocytes differentiates into two equivalent haploid spermatids by meiosis II.

the answer would be   10%