The correct option is B III, II, I, IV
The correct sequence of the events in meiosis is:
III. Synapsis- Synapsis is the pairing of two homologous chromosomes that occurs during meiosis I. It allows pairing-up of homologous pairs prior to their segregation, and chromosomal crossover. It occurs in the zygotene stage.
II. Crossing over- Crossing over is the exchange of chromosome segments between non-sister chromatids of homologous pairs. Crossing over occurs during the pachytene stage.
I. Terminalization- Terminalization of chiasmata occurs in the diakinesis stage of meiosis I. It is the disappearance of chiasmata as it slides towards the tips of the chromosomes due to tight condensation.
IV. Disjunction of chromosomes- The process of breakdown of homologous chromosomes is called disjunction. This process occurs in anaphase I.