The $-OH$ group of methyl alcohol cannot be replaced by chlorine by the action of

In the following reaction sequence,the compound $I$ is:
$I (C_3H_6Cl_2)$ $\xrightarrow{KOH_{(aq)}} II$ $\xrightarrow{(i) CH_3MgBr, (ii) H_2O/H^{+}} III$ $\xrightarrow{Anhy. ZnCl_2 + Conc. HCl}$ gives turbidity immediately.

Write about the oxidation of alcohols.

Which of the following alcohols will undergo dehydration most easily?

An unknown compound $D$ is first oxidized to an aldehyde and then to acetic acid by a dilute solution of $K_2Cr_2O_7$ and $H_2SO_4$. The unknown compound $D$ is:

$CH_3CH_2CH(OH)CH(CH_3)_2 + CH_3COCl \xrightarrow{\text{base}} CH_3CH_2CH(OCOCH_3)CH(CH_3)_2 + HCl$
In the above reaction,if the reactant alcohol is a pure $R$-isomer,the product would: