Crossing over in diploid organism is responsible for

Select the correct statement from the ones given below with respect to dihybrid cross.

Frequency of recombination between gene pairs on same chromosome as a measure of the distance between genes to map their position on chromosome, was used for the first time by

In order to calculate map distance of genes on a chromosome, one must know the

$A$ : Crossing over is exchange of genetic material between non-homologous chromosomes.
$R$ : It produces new linkages.

On the basis of Mendel's work which of the following laws were formulated?

$I.$ Linkage

$II.$ Segregation

$III.$ Incomplete dominance

$IV.$ Independent assortment

Choose the correct option