The correct option is A (CH3)3C−CH2OH
The monohydric alcohol is (CH3)3C−CH2OH
0.44g of a monohydric alcohol when added to methylmagnesium iodide in ether liberates 112cm3 of methane at STP.
At STP 112cm3 of methane corresponds to 11222400=0.005 moles.
0.005 moles of methane corresponds to 0.005 moles of alcohol.
R−OH+CH3−Mg−I→R−O−Mg−I+CH4
0.005 moles of alcohol corresponds to 0.44 g. Hence, the molar mass of alcohol is 0.440.005=88 g/mol. This corresponds to molecular formula (CH3)3C−CH2OH.
With PCC, the same alcohol forms a carbonyl compound that answers silver mirror test. This indicates that the alcohol is primary alcohol.
Note: Silver mirror test (Tollen's reagent, ammoniacal silver nitrate solution) is given by aldehydes but not ketones.