What is the importance of crossing-over?

it increases chromosome condensation.

it increases the likelihood that daughter cells will contain different genetic combinations.

it produces the proteins that are associated with dna in chromosomes.

it separates the homologous chromosomes.

It increases the likelihood that daughter cells will contain different genetic combinations.

Explanation:

All living cells undergo division which can either be Mitosis or Meiosis. Meiosis is peculiar to the cells of sexually-reproducing organisms. Meiosis is the type of cell division that results in daughter cells (gametes) with a reduced number of chromosomes (by half).

In meiosis, particularly during Prophase I, a unique phenomenon whereby chromosomal segment gets exchanged between the non-sister chromatids of homologous chromosomes occurs. This process is called CROSSING-OVER or RECOMBINATION. This crossing-over increases the chance of genetic diversity among sexually-reproducing organisms i.e. the chance that organisms with different genetic contents from the parents will be produced due to the different/recombined genetic combinations in the gametes produced by meiosis.

Crossing-over is unique to only organisms that undergo meiosis, in which the gametes will get recombined and possess different genetic contents as the parents.