The correct option is B 12
Meiocyte is the specialised gamete mother cell of the diploid organisms. Meiocyte is diploid and has 2n number of chromosomes, it undergoes meiosis to produce gametes that will have 'n' number of chromosomes where n represents a single set of chromosomes.
Therefore, if the meiocyte of an organism has 24 chromosomes, then the gamete will have 12 chromosomes.