Crossing-Over Produces Genetic Variation During Prophase I of Meiosis I

Multiple Choice

Crossing-over produces genetic variation during prophase I of meiosis I. This occurs when

A) homologous chromosomes come close together and a rearrangement of alleles occurs.
B) sister chromatids come close together and a rearrangement of alleles occurs.
C) random chromosomes come close together and a rearrangement of alleles occurs.
D) sister chromatids align randomly on the metaphase plate before they are separated.