The group, −NO2 attached to the para nitrophenol of benzenering increases the acidity by electron with drawing effect of−NO2 group. The group, −COCH3 attached to the para acetophenone showsless (−R) effect than −NO2 group. So, it will be less acidic thanpara nitrophenol. Due to −I effect the m - nitrophenol showsless acidic character than option D The group -OMe attached to the phenoxide ion increases theelectron density so it will be less acidic than B.Thus, the correct order is F>D>E>B>C>A