Ans.
Meiosis is type of cell division that occurs in cells of sexually-reproducing individuals. It involves formation of four daughter cells from a single mother cell, having half number (haploid) of chromosomes as present in mother cell.
Meiosis leads to formation of both male and female gametes (mature, haploid germ cells) that fuse together and develop into a diploid, multicellular organisms.
Thus, the correct answer is option b). haploid number of chromosomes and option d). gamete cells.