Thomas Hunt Morgan was awarded the Nobel Prize for his work on:

Two heterozygous parents are crossed. If the two loci are linked,what would be the distribution of phenotypic features in the $F_{2}$ generation for a dihybrid cross?

Genes $A$ and $B$ are linked. What will be the genotype of the offspring produced by a cross between $AB/ab$ and $ab/ab$?

There are three genes $a, b, c$ with percentage of crossing over between $a$ and $b$ is $20\%$,$b$ and $c$ is $28\%$,and $a$ and $c$ is $8\%$. What is the sequence of genes on the chromosome?

Morgan hybridized yellow-bodied,white-eyed females to brown-bodied,red-eyed males and intercrossed their $F_{1}$ progeny. He observed that:
$(a)$ $F_{2}$ ratio deviated significantly from the $9 : 3 : 3 : 1$ ratio.
$(b)$ Both genes did not segregate independently of each other.
$(c)$ Recombinant types are not obtained in $F_{2}$ generation.
$(d)$ Both genes segregate independently of each other.
Select the correct set of statements:

What will be the number of linkage groups in maize if it has $10$ pairs of chromosomes?