. . . . . . $(B)$ . . . . . . used the frequency of recombination between gene pairs on the . . . . . . $(A)$ . . . . . . as a measure of the distance between genes and mapped their position on the chromosome.
$(A) \quad\quad (B)$

The term "linkage" was coined by

Genetic recombination occurs through

Linkage was first observed in

Which of the following statements are correct?

In a certain plant, red flowers $(R)$ are dominant to white flowers $(r)$ and tallness $(T)$ is dominant to dwarfness $(t)$. $A$ heterozygous plant $(RrTt)$ is backcrossed with a double recessive plant $(rrtt)$. If the gene loci for colour and size are situated very close together on the same chromosome, the expected percentage of offspring could be approximately:

Tall Red

Tall White

Dwarf Red

Dwarf White

respectively.