Question

which correctly describes crossing - over?
the process whereby non - sister chromatids exchange genetic material
the process whereby homologous chromosomes are pulled to opposite poles of the cell
the process whereby sister chromatids are pulled to opposite poles of the cell
the process whereby homologous chromosome pairs align randomly along the metaphase plate

Explanation:

Crossing - over occurs during meiosis when non - sister chromatids of homologous chromosomes exchange genetic material, increasing genetic diversity. The other options describe different events in meiosis such as anaphase I (homologous chromosomes pulled to opposite poles), anaphase II (sister chromatids pulled to opposite poles), and independent assortment (homologous chromosome pairs align randomly along the metaphase plate).

Answer:

the process whereby non - sister chromatids exchange genetic material