Correct Answer - B
Both Zn(Hg), HCl and `NH_(2)NH_(2),OH^(-)` can reduce `-COCH_(3)` group to `-CH_(2)-CH_(3)` group, but HCl will also bring about dehydration of alcohol to form alkene. Therefore, appropriate reagent for the conversion is `NH_(2)NH_(2),OH^(-)(B)`.
