How many sperm and ova will be produced from 25 primary spermatocytes and 25 primary oocytes respectively?

The correct option is C 100 sperm and 25 ova

In males, primary spermatocytes are diploid (2N) cells containing 46 chromosomes. Each secondary spermatocyte undergoes meiosis II to produce two spermatids, which later on form two spermatozoa. The spermatids are transformed into spermatozoa (sperms) by the process called as spermiogenesis. After spermiogenesis, sperm heads become embedded in the Sertoli cells, and are finally released from the seminiferous tubules by the process, called as spermiation.

In oogenesis, one oogonium gives rise to primary oocyte and polar body by first meiotic division followed by second meiotic division which produces a single ovum and second polar body.
Thus, 25 primary spermatocytes will produce 100 sperms and 25 primary oocytes will produce 25 ova.

Thus, the correct answer is option D.