Question

what is crossing over?
the movement of genetic material from one chromosome to a nonhomologous chromosome
also referred to as the \independent assortment of chromosomes\
making an rna copy of a dna strand
a direct consequence of the separation of sister chromatids
the exchange of homologous portions of nonsister chromatids

Explanation:

Crossing - over occurs during meiosis when homologous chromosomes pair up. It is the exchange of corresponding segments between non - sister chromatids of homologous chromosomes, which increases genetic diversity. The other options describe different genetic processes: movement to non - homologous chromosomes is translocation, independent assortment is a different principle in meiosis, making an RNA copy of DNA is transcription, and separation of sister chromatids is part of anaphase in cell division.

Answer:

the exchange of homologous portions of nonsister chromatids