The monomer units of nylon-6, 6, nylon 2-nylon-6 are respectively

• A

  $\mathrm{H}_2 \mathrm{NCH}_2 \mathrm{CO}_2 \mathrm{H}, \mathrm{H}_2 \mathrm{~N}-\left(\mathrm{CH}_2\right)_6 \mathrm{NH}_2 ; \mathrm{HO}_2 \mathrm{C}$ $\left.-\mathrm{CH}_2\right)_4 \mathrm{CO}_2 \mathrm{H}, \mathrm{H}_2 \mathrm{NCH}_2 \mathrm{CO}_2 \mathrm{H}$
• B

  $\mathrm{H}_2 \mathrm{NCH}_2 \mathrm{CO}_2 \mathrm{H}, \mathrm{HO}_2 \mathrm{C}+\mathrm{CH}_2 \mathrm{~T}_4 \mathrm{CO}_2 \mathrm{H}$; $\left.\mathrm{H}_2 \mathrm{~N}\left(\mathrm{CH}_2\right)_6, \mathrm{NH}_2, \mathrm{H}_2 \mathrm{~N}+\mathrm{CH}_2\right)_5 \mathrm{CO}_2 \mathrm{H}$
• Correct answer
  C

  $\mathrm{H}_2$ $\left.\mathrm{H}_2 \mathrm{~N}\left(\mathrm{CH}_2\right)_6 \mathrm{NH}_2, \mathrm{HO}_2 \mathrm{C}+\mathrm{CH}_2\right)_4 \mathrm{CO}_2 \mathrm{H}$ $\left.\mathrm{H}_2 \mathrm{NCH}_2 \mathrm{CO}_2 \mathrm{H}, \mathrm{H}_2 \mathrm{~N}+\mathrm{CH}_2\right)_5 \mathrm{CO}_2 \mathrm{H}$
• D

  $\left.\mathrm{H}_2 \mathrm{NCH}_2 \mathrm{CO}_2 \mathrm{H}, \mathrm{H}_2 \mathrm{~N}+\mathrm{CH}_2\right)_5 \mathrm{CO}_2 \mathrm{H}, \mathrm{H}_2 \mathrm{~N}$ $\left.+\mathrm{CH}_2\right)_6 \mathrm{NH}_2, \mathrm{HO}_2 \mathrm{C}-\left(\mathrm{CH}_2\right)_4-\mathrm{CO}_2 \mathrm{H}$

Solution

Monomers unit of nylon-6, 6 are Hexamethylene diamine, $$ \mathrm{NH}_2\left(\mathrm{CH}_2\right)_6 \mathrm{NH}_2 \text { and adipic acid }\left(\mathrm{CH}_2\right) $$
Monomers unit of nylon-2-nylon-6 are glycine $\mathrm{NH}_2 \mathrm{CH}_2 \mathrm{COOH}$ and amino caproic acid $\mathrm{NH}_2\left(\mathrm{CH}_2\right)_5 \mathrm{COOH}$. Hence, option (3) is correct.

Hence, the correct answer is option: 'C'.