The correct option is A mitosis
Mitosis is the cell division where the number of chromosomes remain the same as the parent cell.
Meiosis is the cell division in which the number of chromosomes in the daughter cells reduce by half from its parent cell.
In binary fission and fragmentation, the number of chromosomes remain the same but it doesn’t occur in plants of division bryophyta.
Antherozoids and eggs are the male and female gametes in bryophytes. They are produced from the gametophyte which is haploid (n) and multicellular. The gametes are also haploid (n) in nature. As there are the same number chromosomes in the cells of the gametophyte and gametes, the gametes are produced by mitosis.