Which method can be used to determine the location of specific genes on a chromosome?

Who coined the term 'linkage'?

The scientists who proposed the theory of linkage are

In maize, colored endosperm $(C)$ is dominant over colorless $(c)$ and full endosperm $(R)$ is dominant over shrunken $(r)$. When a test cross is performed on the $F_1$ generation, the following results are obtained:
Colored and Full = $45\%$
Colored and Shrunken = $5\%$
Colorless and Full = $4\%$
Colorless and Shrunken = $46\%$
Based on this data, what is the distance between the two non-allelic genes (in $units$)?

$A$ pure breeding pea plant with the dominant phenotype of character $A$ and recessive phenotype of character $B$ was crossed with another pure breeding plant with the recessive phenotype of $A$ and dominant phenotype of character $B$. An offspring of this cross was crossed with a homozygous recessive for both the characters $A$ and $B$. The following results were obtained:
$22$ were phenotypically dominant for $A$ and recessive for $B$.
$4$ were phenotypically dominant for both $A$ and $B$.
$4$ were phenotypically recessive for both $A$ and $B$.
$24$ were phenotypically recessive for $A$ and dominant for $B$.
These results show that:

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: