b
The iodoform test is positive for alcohols with formula \(\mathrm{R}-\mathrm{CHOH}-\mathrm{CH}_{3}\). Among \(\mathrm{C}_{6} \mathrm{H}_{14} \mathrm{O}\) isomers, the ones with posith positive iodoform test are:

\(I.\)  \(\mathrm{CH}_{3}-\mathrm{CH}_{2}-\mathrm{CH}_{2}-\mathrm{CH}_{2}-\mathrm{CHOH}-\mathrm{CH}_{3}\) -\(2-\)Hexanol

\(II.\)  \(\mathrm{CH}_{3}-\mathrm{CH}_{2}-\mathrm{CH}\left(\mathrm{CH}_{3}\right)-\mathrm{CHOH}-\mathrm{CH}_{3}\)-\(3-\) Methyl\(-2-\)pentanol

\(III.\)  \(\left(\mathrm{CH}_{3}\right)_{2} \mathrm{CH}-\mathrm{CH}_{2}-\mathrm{CHOH}-\mathrm{CH}_{3}\)\(4-\)methyl\(-2-\)pentanol

\(IV.\)  \(\left(\mathrm{CH}_{3}\right)_{3} \mathrm{C}-\mathrm{CHOH}-\mathrm{CH}_{3}\)\(3,3\) - Dimethyl\(-2-\)butanol