In which stage the chromosomes combine and begin to separate from each other during meiosis cell division?

The correct option is B Diplotene
The chromosomes combine and begin to separate from each other during meiosis cell division in the diplotene stage. The synaptonemal complex degrades and homologous chromosomes separate from each other. The chromosomes themselves uncoil a bit, allowing some transcription of DNA. However, the homologous chromosomes of each bivalent remain tightly bound at chiasmata, the regions where crossing-over occurred. The chiasmata remain on the chromosomes until they are severed at the transition to anaphase I.