Resulting chromosomes numbers in each of the 4 gametes were 23, 23, 24, and 22. abnormal occurrence in meiosis

the separation of the chromosomes occurs in the first stage of meiosis. the nonseparation of these chromosomes would result in abnormal gametes(all of them) so this defect could have arisen if and only if the separation of chromosomes in one of the cell formed after meiosis1 did not separate during meiosis2. so the ans is 4