$w.r.t.$ the question asked, $1$ -pentanol has maximum number of carbons, so it is least soluble in water. $\{$ extent of $H-$ bonding decreases $\}$
નીપજ $(C)$ શું હશે ?
$1. {{H}_{3}}C-\overset{+}{\mathop{O}}\,{{H}_{2}}\to CH_{3}^{+}+{{H}_{2}}O$
$2. (CH_3)_3 C - \overset{+}{\mathop{O}}\,{{H}_{2}} \to (CH_3)_3 C^+ + H_2O$
$3. (CH_3 )_2CH - \overset{+}{\mathop{O}}\,{{H}_{2}} \to (CH_3)_2 CH^+ + H_2O$