Chromosomes exchange genetic information during prophase i by

The answer is crossing over. Sister chromosomes of the homologous  chromosomes exchange parts of their arms after forming an attachment joint called a chiasma. This results in recombination of genetic material between the attached chromosomes. This phenomenon is responsible for increased variation in the offsprings from the formed gametes

Chromosomes exchange genetic information during prophase I by a process called cross over. This process occurs in the first division of meiosis in prophase I, where two chromosomes of a homologous pair exchange segements with each other. It creates new combinations of genes in the gametes that are found in either parent and therefore contributing to what we call genetic diversity or genetic variation among organisms.

C. a mature ovule of a plant.

Yes yes yes very good