Scientists hypothesize that over millions of years the y chromosome has lost genes to the x chromosome. during what stages of meiosis might this have happened

Prophase 1

Meiosis occurs in a series of different phases and creates genetically unique reproductive cells. The process which helps make meiotic cells genetically different and occurs during prophase I, but not during prophase II, is crossing over (C). Crossing over is the exchange of genetic material between two homogenous chromosomes. It is one of the final phases of prophase I. This process is called synapsis. It occurs when the matching regions on the matching chromosomes break and then reconnect to the other chromosome

The answer is b. hope this !