which is required for sexual reproduction?\nmitosis\nbinary fission\ndiploid cell production\nmeiosis

Brief Explanations:

Meiosis is the cell - division process that produces gametes (sperm and egg cells) which are essential for sexual reproduction. Mitosis is for growth and asexual cell - replacement, binary fission is a form of asexual reproduction in prokaryotes, and diploid cell production alone does not directly relate to the key process of sexual reproduction.

Answer:

D. meiosis