Question
$CH_3CHO \xrightarrow{(i)\, CH_3MgBr \quad (ii)\, H_2O^+} A \xrightarrow{\text{Conc. } H_2SO_4 \quad \Delta} B \xrightarrow{(i)\, B_2H_6 \quad (ii)\, H_2O_2,\, OH^-} C$
A and C are
$CH_3CHO \xrightarrow{(i)\, CH_3MgBr \quad (ii)\, H_2O^+} A \xrightarrow{\text{Conc. } H_2SO_4 \quad \Delta} B \xrightarrow{(i)\, B_2H_6 \quad (ii)\, H_2O_2,\, OH^-} C$
A and C are