Each pair forms ideal solution except:
A. ${C_2}{H_{5\,}}Br\,and\,{C_2}{H_5}I$
B. ${C_2}{H_{5\,}}Cl\,and\,{C_2}{H_5}Br$
C. ${C_6}{H_6}\,and\,{C_6}{H_5}C{H_3}$
D. ${C_2}{H_6}I\,and\,{C_2}{H_5}OH$

Hint: In nature, the substances exist as pure substances or in the form of mixtures. When two or more substances mix they form a mixture. The mixtures can be homogeneous and nonhomogeneous based on the properties of the intermixing substances. The mixture can be separated based on the properties that the mixture shows.

Complete step by step answer:
The substances either exist as pure matter or in the form of substance. The properties of the final mixture and the intermixing substance decide how the mixture can be processed.
The substance in the small quantity is the solute while the substance in the larger quantity is the solvent. After the formation of the mixture, there are various methods for the separation of the mixtures to retrieve the original substances which were used for the formation of the mixture.
An ideal solution is a solution in which we have the distinction in the type of molecules that are present in the solution, but it is not like the ideal gas in which one molecule is unaffected by the other, in an ideal solution the molecules in the solution exert force on one another.
If the case where the forces are the same for all the molecules then the solution is said to be an ideal solution in that case.
In the above question, the pairing with ethyl alcohol seems most divergent from this concept due to the presence of the polarity of the molecules involved. The factor of the hydrogen bonding also comes to the place since the hydroxyl group on ethyl alcohol.

So, the correct answer is Option D.

Note: Solvation and solubility are two different concepts, Solvation is a kinetic process and is quantified based on the rate while solubility quantifies the dynamic equilibrium.
Solubility is related to the dynamic equilibrium state achieved when the rate of dissolution and the rate of precipitation is the same.
The concept of dissolve is generally followed in chemistry which states that a polar solvent will dissolve a polar solute while a nonpolar solvent will dissolve a nonpolar solute.